Download or read book Investigations Into the Impact of Transported Particles on Air Pollution and Climate Using Aerosol Time of flight Mass Spectrometry written by Andrew Phillip Ault and published by . This book was released on 2010 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric aerosols have a significant impact on human health and climate, yet the full scope of these influences are only beginning to be discovered and characterized. To understand these impacts, detailed in-situ measurements of the physical, chemical, and optical properties of aerosols are necessary. Aerosol time-of-flight mass spectrometry (ATOFMS) provides the ability to measure chemical, physical, and optical properties of single particles in real-time. This dissertation uses ATOFMS to explore both the properties and evolution of particles as they are transported over local to global distances. The results of numerous field studies are utilized to explore the changes to these particles as they travel through the atmosphere from their source to eventual deposition. Local to regional scale transport of particles was observed from a number of perspectives in this dissertation. Particles regionally transported from the Ports of Los Angeles and Long Beach to San Diego were identified chemically as ship and truck emissions and shown to overwhelm local sources during peak transport conditions. Ship emissions were studied in detail at the Port of Los Angeles by characterizing individual ship plumes at a site adjacent to the main channel. Mobile laboratory measurements demonstrated the variation in particle concentrations and composition on a local-to-regional level. On the intercontinental-to-global scale, Asian dust was observed in precipitation samples collected in the Sierra Nevada Mountains during orographic precipitation. The incorporation of the long range-transported dust might enhance precipitation, which may alter California's precipitation patterns and water supply. The outflow of particles from Asia to North America were measured on a remote island off Korea, and the sources and aging of particles in Chinese urban, Chinese dust, and Korean air masses were compared to marine air masses. Lastly, ATOFMS studies from sites across North America, Asia, Europe, and Africa were compared to determine similarities and differences in size-resolved chemical mixing state of particles across numerous types of sampling sites, with the objective being to provide information for global climate models to more accurately represent particles. Taken together these results provide an increased understanding of particle chemistry and transport on the scale of meters-to-continents.
Download or read book Characterization of Particulate Pollution by Aerosol Mass Spectrometry written by Courtney Leigh Herring and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric aerosols impact human health, climate, and air pollution and arrive in the atmosphere by countless number of sources. One of the largest uncertainties in understanding these impacts is due to limitations in our understanding of the organic aerosol (OA) components. To understand this complex mixture of thousands of compounds accurate high-resolution chemical speciation is needed. An Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS or HR-AMS) was deployed in two separate month-long studies to measure atmospheric particulate pollution. The first study, at the Lovelace Respiratory Research Institute (LRRI), focused on the measurement of gasoline and diesel engine exhaust under various loads and dilutions in controlled chamber experiments. HR-AMS data demonstrated clean signal associated with 53 polycyclic aromatic hydrocarbon (PAH) compounds. PAHs are of interest due to their carcinogenic implication and negative health effects especially when associated with submicron particles. From this work a novel methodology was developed for quantifying these compounds by their molecular ion signal (P-MIP). In the second study, conducted in Yakima, WA, ambient wintertime pollution was characterized and the OA components were deconvolved using positive matrix factorization (PMF). This investigation resulted in the identification of two new amine associated factors which were identified by mass spectra peaks from six dominant amine ions (C3H8N+, C2H6N2+, C4H 10N+, C3H8N2 +, C5H12N+, and C6H 14N+). Amine ions are of interest to atmospheric research because of their implications on climate and formation of new particles. The unifying implication from both studies was the utilization of the HR-AMS to identify atmospheric pollutants that continue to generate ongoing research interests (due to their impacts on climate, pollution, or human health) and are typically difficult to measure by the HR-AMS. Additionally, included in this dissertation are four examples of science/engineering related inquiry-based lessons that were developed to relate well with my own Master's research field and implemented into three high school science and math classrooms over the course of a two year NSF STEM Fellowship. Lastly, a two-year long case study following qualitative and quantitative data from 296 students one of these activities provides examples of the positive impact by these types of developed activities.
Download or read book Aerosol Pollution Impact on Precipitation written by Zev Levin and published by Springer Science & Business Media. This book was released on 2008-09-30 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: Life on Earth is critically dependent upon the continuous cycling of water between oceans, continents and the atmosphere. Precipitation (including rain, snow, and hail) is the primary mechanism for transporting water from the atmosphere back to the Earth’s surface. It is also the key physical process that links aspects of climate, weather, and the global hydrological cycle. Changes in precipitation regimes and the frequency of extreme weather events, such as floods, droughts, severe ice/snow storms, monsoon fluctuations and hurricanes are of great potential importance to life on the planet. One of the factors that could contribute to precipitation modification is aerosol pollution from various sources such as urban air pollution and biomass burning. Natural and anthropogenic changes in atmospheric aerosols might have important implications for precipitation by influencing the hydrological cycle, which in turn could feed back to climate changes. From an Earth Science perspective, a key question is how changes expected in climate will translate into changes in the hydrological cycle, and what trends may be expected in the future. We require a much better understanding and hence predictive capability of the moisture and energy storages and exchanges among the Earth’s atmosphere, oceans, continents and biological systems. This book is a review of our knowledge of the relationship between aerosols and precipitation reaching the Earth's surface and it includes a list of recommendations that could help to advance our knowledge in this area.
Download or read book Determination of the spatial and temporal variability of size resolved PM2 5 composition and mixing state in multiple regions in California written by Kimberly Prather and published by California Air Resources Board. This book was released on 2009-12-01 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Final report for California Air Resources Board contract 04-336. For an abstract and link to full text, please see: http://www.arb.ca.gov/research/single-project.php?row_id=64974
Download or read book Aerosols in Atmospheric Chemistry written by Yue Zhang and published by American Chemical Society. This book was released on 2022-04-01 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: The uncertainties in the aerosol effects on radiative forcing limit our knowledge of climate change, presenting us with an important research challenge. Aerosols in Atmospheric Chemistry introduces basic concepts about the characterization, formation, and impacts of ambient aerosol particles as an introduction to graduate students new to the field. Each chapter also provides an up-to-date synopsis of the latest knowledge of aerosol particles in atmospheric chemistry.
Download or read book Using single particle mass spectrometry and isotope measurements to determine the contributions of ship emissions to ambient PM in La Jolla California written by Mark Thiemens and published by California Air Resources Board. This book was released on 2008-12-31 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Final report for California Air Resources contracts 04-347 and 05-346. For abstract and link to full text, please visit: http://www.arb.ca.gov/research/single-project.php?row_id=64430
Download or read book Research Priorities for Airborne Particulate Matter written by National Research Council and published by National Academies Press. This book was released on 2004-10-22 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1997, the U.S. Environmental Protection Agency (EPA) established regulatory standards to address health risks posed by inhaling tiny particles from smoke, vehicle exhaust, and other sources. At the same time, Congress and the EPA began a multimillion dollar research effort to better understand the sources of these airborne particles, the levels of exposure to people, and the ways that these particles cause disease. To provide independent guidance to the EPA, Congress asked the National Research Council to study the relevant issues. The result was a series of four reports on the particulate-matter research program. The first two books offered a conceptual framework for a national research program, identified the 10 most critical research needs, and described the recommended timing and estimated costs of such research. The third volume began the task of assessing initial progress made in implementing the research program. This, the fourth and final volume, gauged research progress made over a 5-year period on each of the 10 research topics. The National Research Council concludes that particulate matter research has led to a better understanding of the health effects caused by tiny airborne particles. However, the EPA, in concert with other agencies, should continue research to reduce further uncertainties and inform long-term decisions.
Download or read book New Insights Into Single particle Mixing State Using Aircraft Aerosol Time of flight Mass Spectrometry written by Kerri Anne Pratt and published by . This book was released on 2009 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric aerosols strongly influence the energy balance of the Earth and the hydrological cycle by scattering and absorbing radiation and acting as cloud condensation and ice nuclei. The climate and human health impacts of aerosols are strongly dependent on particle size, chemical composition, and mixing state. During transport in the atmosphere, aerosol particles undergo physical and chemical transformations (atmospheric aging) through heterogeneous reactions with trace gases and gas-particle partitioning of semivolatile species. The size-resolved chemical composition of individual particles may be examined in real-time using aerosol time-of-flight mass spectrometry (ATOFMS). A smaller ATOFMS with increased data acquisition capabilities was developed for aircraft-based studies. Particle volatility was examined through ground-based measurements during the Study of Organic Aerosols in Riverside, CA (SOAR), and vertical mixing state profiles and cloud residues were examined through flight-based measurements during the Ice in Clouds Experiment - Layer Clouds (ICE-L). An automated thermodenuder (TD) was coupled to the aircraft (A)-ATOFMS to provide the first real-time, individual-particle size and volatility-resolved chemical composition measurements. This work provided insight into the volatility of secondary species, as well as the sources and chemistry of ambient particle cores. Seasonal differences in the volatility of amine species were attributed to the formation of aminium sulfate and nitrate salts in the summer. Oligomeric species were detected in real-time for the first time in individual ambient aerosol particles; increased oligomer ion intensities were associated with increased particle acidity and heating. During ICE-L, vertical profiles of particle types, such as soot, mixed with secondary species, such as sulfuric acid, were examined. For cloud sampling, a counterflow virtual impactor was utilized in series with the A-ATOFMS to examine the residues of cloud droplets and ice crystals. This resulted in the first in-situ detection of biological particles in high altitude ice clouds influenced by long-range transported dust. Playa salts were observed to serve as cloud condensation nuclei and were preferentially observed as residues of large droplets.
Download or read book Aerosol Time of flight Mass Spectrometry ATOFMS as a Real time Monitor of Individual Aerosol Particles in Field Studies written by Kimberly A. Prather and published by . This book was released on 2001 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research Priorities for Airborne Particulate Matter written by Committee on Research Priorities for Airborne Particulate Matter and published by National Academies Press. This book was released on 1998-05-14 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: New National Ambient Air Quality Standards for airborne particles smaller than 2.5 micrometers, called PM2.5, were issued by the U.S. Environmental Protection Agency (EPA) amidst scientific uncertainty and controversy. In response to a request from Congress, Research Priorities for Airborne Particulate Matter, the first of four books in a series, offers a conceptual framework for an integrated national program of particulate-matter research, identifies the 10 most critical research needs linked to key policy-related scientific uncertainties, and describes the recommended timing and estimated costs of such research. The committee concludes that EPA should devote more resources to investigating the relationships between fixed-site outdoor monitoring data and actual human breathing-zone exposures to ambient particulate matter and to identifying the most biologically important constituents and characteristics of particulate matter through toxicological studies. The recommended research activities are critical to determining actual exposures of human subpopulations most susceptible to harm from the most hazardous constituents of particulate matter. Future research will be an investment in public health and a means to ensure that resources spent on control technology and regulatory compliance will have a reasonable probability of success.
Download or read book Source Profiling and Apportionment of Airborne Particles written by Philip Joseph Silva and published by . This book was released on 2000 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Toxicity of Atmospheric Aerosols Methodologies Assays written by Fobang Liu and published by American Chemical Society. This book was released on 2023-06-06 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric aerosols, or particulate matter (PM), are liquid or solid particles suspended in the air. Exposure to ambient PM is associated with multiple diseases and accounts for millions of premature deaths today. Although recognized as an important public health problem, PM’s toxicity and toxicological mechanisms are yet to be understood. Various methodologies and assays (i.e., procedures to determine the composition, quantity, or quality of a substance or a mixture) have been developed or employed to understand the components and characteristics of PM that best determine its toxicity. Efforts have also been spent to study the mechanisms of cellular signaling, stress, response, and physiological change, as well as complex multi-tissue effects upon PM exposure. These assays are diverse, spanning from in vitro acellular assays (i.e., chemical assays) to in vitro cellular and in vivo assays. Given that various methodologies and assays have been developed or employed, this digital primer aims to introduce the methodologies and fundamental principles used to study atmospheric aerosols’ toxicity and emerging new techniques. A comprehensive literature review of the scientific findings using these methodologies and assays is not the focus of this primer. The target audiences are senior undergraduates or beginning graduate students unfamiliar with aerosol science and toxicity measurements. An introductory overview of atmospheric aerosols and the motivations to study their toxicity before a detailed discussion of methodologies and assays in the toxicity research of atmospheric aerosols is provided. Beyond this, Toxicity of Atmospheric Aerosols: Methodologies & Assays serves as an assembly of the various methodologies and assays used in the toxicity research of atmospheric aerosols, saving readers time compared to searching from scattered resources.
Download or read book Using Aerosol Time of flight Mass Spectrometry ATOFMS Data to Gain New Insights Into the Temporal Profiles Composition and Evolution of Individual Particles in the Troposphere written by Don-Yuan Liu and published by . This book was released on 2000 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances and Applications of Mass Spectral Techniques for the Characterization of Atmospheric Aerosol Particles written by Lindsay Erighn Hatch and published by . This book was released on 2012 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerosol particles are ubiquitous in the atmosphere and induce significant impacts on human health and climate that depend on their physical and chemical properties, such as size, composition, and mixing state (chemical associations). Measurements of aerosol composition at the single-particle level are necessary to better understand these effects. Aerosol time-of-flight mass spectrometry (ATOFMS) is able to monitor the size and chemical composition of individual particles in real time. In this doctoral research, ATOFMS analysis was extended to identify new mass spectral markers and improve the potential for quantitative measurements. Development of novel instrumentation was also undertaken. Ion markers indicative of organosulfate compounds were identified in ATOFMS mass spectra collected in Atlanta, GA. In this study, the mixing state and temporal behavior of particulate organosulfate compounds were observed for the first time. Organosulfates were overwhelmingly detected in carbonaceous submicron particles and the temporal trends indicated that they likely formed by the daytime oxidation of isoprene followed by aqueous reaction with sulfate overnight. These results highlight the roles of mixing state and multi-phase reactivity on the formation of secondary organic aerosols. ATOFMS measurements of thermally-conditioned aerosol residuals obtained during the 2005 Study of Organic Aerosols in Riverside, CA were analyzed to determine the impacts of atmospheric aging on the laser desorption/ionization process. Coatings of secondary species suppressed the ionization efficiency, thereby impacting the mass spectral peak areas; however, a novel analysis method was found to correct these artifacts and produced strong agreement with collocated quantitative instrumentation. This new analysis technique was then applied to investigate the mixing-state dependence of aerosol volatility observed in Riverside. It was observed that particulate nitrate evaporated at different temperatures from different particle types (e.g., organic vs. biomass burning), which may influence the regional transport of nitrate species. ATOFMS provides important insights into size-resolved particle sources; however it heavily fragments most organic species, resulting in loss of the molecular information. Therefore, a novel chemical ionization mass spectrometer was developed to better characterize the molecular organic aerosol constituents. In particular, an ion funnel was incorporated into a home-built proton-transfer-reaction mass spectrometer. Initial characterization studies and ion simulations indicated that the ion funnel can provide high-efficiency ion transfer from the ionization region to the mass spectrometer. These results demonstrate the potential for this instrument to ultimately achieve highly sensitive analyses of organic aerosols.
Download or read book Analysis Concepts Of Aerosols by On Line Aerosol Mass Spectrometry written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It is known that aerosols have an impact on climate, air quality and health. To better characterize these effects, the knowledge of the aerosol particle properties, such as size and chemical composition, at the individual level is needed. Toward this purpose, a Single Particle Aerosol Laser Mass Spectrometer (SPALMS) has been designed and developed to characterize in details the organic fraction of particles. The instrument samples the aerosol with a nozzle system and sizes particles individually by laser velocimetry. The single particle constituents are then volatilized (desorption) and ionized (ionization) by laser. The resulting cations and anions are analyzed with a bipolar time-of-flight mass spectrometer. The resulting mass spectra provide a "fingerprint" of the particle composition. Thus the SPALMS instrument evaluates the mixing state, external versus internal, of the aerosol and allows the investigation of the chemical composition size dependency of the particles. The desorption and ionization steps are critical to obtain a good qualitative chemical analysis of the particle. Indeed many processes take place during these steps which fragment and alter the initial molecules in the particle. The simultaneous desorption and ionization with a single laser (337 nm) combined with a bipolar mass spectrometer is well suited for the analysis of mineral particles. On the other hand, organics in particles are better analyzed by operating first the constituents desorption with an infra-red laser (10.6 micrometers) and then the ionization shortly after with an ultra-violet laser (248 nm). Indeed molecules are softly ionized via a SPI or REMPI process. In this manner the resulting mass spectra are more representative of the particle composition since organics are less fragmented. As the SPALMS instrument involves many different measurement steps based of very different principles, it is equipped with many data acquisition devices (up to 12 channels) to record the correspo.
Download or read book Particulates Matter written by Vikram Rao and published by Elsevier. This book was released on 2020-11-28 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: A title in the Emerging Issues in Analytical Chemistry series, Particulates Matter: Impact, Measurement, and Remediation of Airborne Pollutants provides the latest technical findings in the study of particulate matter (PM). It links these findings to awareness-raising and actionable schemes for legislated remediation and engineered solutions. Written in an engaging and informative manner, the book begins with a multi-disciplinary overview of the major sources and unique classes of PM, detection techniques, and their impact, including molecular changes resulting in health effects. It then goes one step further by proposing and examining the means to curtail and contain PM generation and ameliorate their impacts. Particulates Matter: Impact, Measurement, and Remediation of Airborne Pollutants offers a high-quality reference guide to PM that will greatly benefit technology leaders in environmental compliance groups, epidemiologists and other public health professionals focused on pollution and health, and researchers and scholars working in pollution, climate change, and urbanization. It may also be useful to advanced undergraduate and early graduate students in environmental sciences. Includes a summary of the current knowledge on nanoparticles as pollutants and their negative health effects Provides a framework for the evolution and maturation of air pollution characterization and mitigation Describes an integrated set of engineered solutions that account for the concatenated relationships between technology, policy, and society necessary for long-term success
Download or read book Air Pollution Studies written by G Passerini and published by WIT Press. This book was released on 2020-05-18 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Air pollution issues remain one of the most challenging problems facing society. This wide-ranging collection of high-quality works contains valuable research on issues related to the modelling, monitoring and management of air pollution. The papers included in this book develop the fundamental science of air pollution. Scientific knowledge derived from well-designed studies needs to be allied with further technical and economic studies in order to ensure cost-effective and efficient mitigation. Increasingly, it is being recognised that the outcome of such research needs to be contextualised within well-formulated communication strategies that help policymakers and citizens to understand and appreciate the risks and rewards arising from air pollution management. Details of the widespread nature of the air pollution phenomena and in-depth explorations of their impacts on human health and the environment are covered in this book.
