Download or read book Development and Use of Particle Into Liquid Sampling Time of flight Mass Spectrometry PILS ToF for Characterization of Aerosol Particles written by Christopher Holmes Clark and published by . This book was released on 2012 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation introduces and makes use of the Particle-into-Liquid-Sampler coupled to a Time-of-Flight mass spectrometer (PILS-ToF), a new instrumental method used here to provide new chemical characterization information on secondary organic aerosol (SOA). The PILS-ToF instrument improves upon drawbacks found in current state-of-the-art mass spectral chemical characterization methods to include lack of time resolution and ion fragmentation by electron impact ionization in the Aerodyne Aerosol Mass Spectrometer (AMS). The functionality of the PILS-ToF for collection and response to SOA particle formation is validated against a scanning mobility particle sizer (SMPS), a widely accepted and standardized physical chemical characterization instrument, for a well characterized SOA formation experiment, dark ozonolysis of [alpja]-pinene. The PILS-ToF is also used to lend insight into oligomer growth during the NO photo-oxidation of isoprene. It is of atmospheric importance to study SOA formation from isoprene as it is globally the most abundant non-methane hydrocarbon in the ambient. SOA from isoprene is further studied using the PILS-ToF as part of the suite instrumentation at the University of California, Riverside, College of Engineering, Center for Environmental Research and Technology (CE-CERT) atmospheric chamber providing a complete chemical and physical characterization of SOA formed by isoprene with various oxidants under a myriad of oxidant concentration conditions. In addition, the PILS-ToF is used, again in tandem with other chemical and physical characterization methods at CE-CERT, to probe temperature effects on SOA formation from isoprene under many different oxidizing conditions. Finally, the PILS-ToF is used to provide new mechanistic information on SOA formation from trimethylamine and tributylamine, two tertiary amines emitted from anthropogenic and animal husbandry processes. For these two teriary amines the PILS-ToF provides evidence of oligomerization giving a potential explanation to the high SOA yields from these parent compounds.
Download or read book Development Characterization and Refinement of a Transportable Aerosol Time of flight Mass Spectrometer written by Tas Dienes and published by . This book was released on 2003 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Aerosol Particles Containing Sulfur and Nitrogen Species Using Aerosol Time of flight Mass Spectrometry ATOFMS written by Kimberly Louise Salt and published by . This book was released on 1995 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fine Particles written by Benjamin Y.H. Liu and published by Elsevier. This book was released on 2012-12-02 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fine Particles: Aerosol Generation, Measurement, Sampling, and Analysis is a collection of technical papers presented at the Symposium on Fine Particles held in Minneapolis, Minnesota, on May 28-30, 1975. The symposium aims to explore the developments in instrumentation and experimental techniques for aerosol studies. This book is organized into four parts encompassing 34 chapters that focus on fine particles below about 3.5 μm in diameter. Part I presents the research and development in Europe and Japan on fine particles and aerosols, as well as the aerosol standards development work at the Particle Technology Laboratory, University of Minnesota. This part also includes calibration studies on condensation nuclei counters and the diffusion battery. Significant chapters in Part II are devoted to the common techniques for generation of aerosols of various sizes, from fine particles to monodisperse aerosols. This part further looks into the equipment limitations and problems in producing fine particle aerosols for life testing air cleaning systems and for weather modification experimentation. Part III describes the techniques and equipment used for size-selective aerosol sampling in terms of the design principles applied, the correspondence between design and performance of specific samplers, their applicability to field conditions, and their ability to satisfy sampler acceptance criteria. Part IV deals first with the methods for determination of aerosol properties, including their optical, electrical, and spectral properties. Other chapters examine the principles, mode of operation, and application of processes and instruments for aerosol studies.
Download or read book Anthropogenic Particulate Source Characterization and Source Apportionment Using Aerosol Time of flight Mass Spectrometry written by Stephen Mark Toner and published by . This book was released on 2007 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Methods of measuring the chemical and physical properties of aerosols as well as proper source apportionment of ambient particles are necessary to provide insight as to the roles they play in the environment and their impact on human health. In addition, the ability to apportion ambient particles quickly and accurately will be very helpful for environmental and health agencies and for monitoring and enforcing emission standards by allowing such agencies to determine the primary source of aerosols in their monitoring areas. The goal of this dissertation is to provide a new approach for aerosol source apportionment using aerosol time-of-flight mass spectrometry (ATOFMS) single particle data. This goal was accomplished by determining unique mass spectral signatures for specific aerosol sources and by developing these signatures into a source signature library in which ambient ATOFMS data can be matched and apportioned. The creation of the source signature library (SSL) began with the characterization of specific sources themselves. Heavy duty diesel vehicle (HDDV) emissions were characterized using ATOFMS from a dynamometer study. The particle types detected for HDDVs were compared to those from a previous dynamometer study of gasoline powered light duty vehicles (LDV) to see if HDDV and LDV particles can be distinguished. A SSL was then created for the HDDV and LDV emissions to test the ability to properly apportion between the two sources on ambient ATOFMS data collected next to a major freeway using a SSL matching technique. This work demonstrated that the two sources are readily distinguishable in a fresh emission environment, and that the matching method is a valid means for apportioning ATOFMS data. The SSL was then extended for multiple specific sources as well as for non-source specific particles and was used to apportion the same freeway study particles; showing that the source matching method is able to accurately distinguish different particle sources and that there can be a large contribution from sources other than vehicles near a major freeway. Lastly, the SSL matching method was used to apportion ambient aerosols for two major non-US cities to show that the SSL matching technique is applicable to worldwide ambient ATOFMS data.
Download or read book The Analysis of Aerosol Time of flight Mass Spectrometry Data written by David Philip Fergenson and published by . This book was released on 2001 with total page 302 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 The Design and Construction of an Aerosol Time of flight Mass Spectrometer for Ambient Aerosol Analysis written by Trent Eric Nordmeyer and published by . This book was released on 1995 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Further Development and Application of Laser Desorption Ionization LDI Using Aerosol Time of flight Mass Spectrometry ATOFMS written by Ryan Jay Wenzel and published by . This book was released on 2004 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Atmospheric Aerosol Processes Using Single Particle Mass Spectrometry written by Jeffrey Robert Whiteaker and published by . This book was released on 2002 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Characterization of Atmospheric Aerosols written by and published by . This book was released on 1998 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project of the Los Alamos National Laboratory (LANL). The objective of this collaborative research project is the measurement and modeling of atmospheric aerosols and heterogeneous (gas/aerosol) chemical reactions. The two major accomplishments are single particle characterization of tropospheric particles and experimental investigation of simulated stratospheric particles and reactions thereon. Using aerosol time-of-flight mass spectrometry, real-time and composition measurements of single particles are performed on ambient aerosol samples. This technique allows particle size distributions for chemically distinct particle types to be described. The thermodynamics and chemical reactivity of polar stratospheric clouds are examined using vapor deposited thin ice films. Employing nonlinear optical methods, as well as other techniques, phase transitions on both water and acid ices are monitored as a function of temperature or the addition of gases.
Download or read book Single Particle Analysis of Transient Variations Occurring in Atmospheric Aerosols written by Christopher Alan Noble and published by . This book was released on 1999 with total page 1230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Ambient Automobile and Diesel Aerosols Utilizing Aerosol Time of Flight Mass Spectrometry written by David Alan Sodeman and published by . This book was released on 2004 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Ambient Aerosols at the San Francisco International Airport Using BioAerosol Mass Spectrometry written by M. Frank and published by . This book was released on 2006 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The BioAerosol Mass Spectrometry (BAMS) system is a rapidly fieldable, fully autonomous instrument that can perform correlated measurements of multiple orthogonal properties of individual aerosol particles. The BAMS front end uses optical techniques to nondestructively measure a particle's aerodynamic diameter and fluorescence properties. Fluorescence can be excited at 266nm or 355nm and is detected in two broad wavelength bands. Individual particles with appropriate size and fluorescence properties can then be analyzed more thoroughly in a dual-polarity time-of-flight mass spectrometer. Over the course of two deployments to the San Francisco International Airport, more than 6.5 million individual aerosol particles were fully analyzed by the system. Analysis of the resulting data has provided a number of important insights relevant to rapid bioaerosol detection, which are described here.
Download or read book New Approaches for the Chemical and Physical Characterization of Aerosols Using a Single Particle Mass Spectrometry Based Technique written by Matthew Todd Spencer and published by . This book was released on 2007 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comparison of mass spectra generated from petrochemical particles was made to light duty vehicle (LDV) and heavy duty diesel vehicle (HDDV) particle mass spectra. This comparison has given us new insight into how to differentiate between particles from these two sources.
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 Quantitative Analysis of Aerosol Time of flight Mass Spectrometry Data Using YAADA written by Jonathan O. Allen and published by . This book was released on 2004 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
