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Book Development and Use of Particle Into Liquid Sampling Time of flight Mass Spectrometry  PILS ToF  for Characterization of Aerosol Particles

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.

Book Characterization of Aerosol Particles Containing Sulfur and Nitrogen Species Using Aerosol Time of flight Mass Spectrometry  ATOFMS

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:

Book Development and Characterization of Two Versions of a New Single Particle Mass Spectrometer for Organic Aerosol Analysis that Incorporate a 3D Ion Trap

Download or read book Development and Characterization of Two Versions of a New Single Particle Mass Spectrometer for Organic Aerosol Analysis that Incorporate a 3D Ion Trap written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerosol particles are ubiquitous throughout the atmosphere and play an important role in human health, climate, and the chemistry of the atmosphere. A significant mass fraction of these particles is composed of organic species, which remain poorly characterized due to the number and diversity of species present. This thesis describes the development and characterization of two versions of a new single particle mass spectrometer with a 3D ion trap for organic aerosol studies. Version I combines CO2 laser desorption and electron impact ionization in an ion trap. Mass spectra obtained for four species are comparable to NIST EI spectra. Tandem mass spectrometry studies are also demonstrated. The effects of vaporization energy, ionization delay time, and electron pulse width on the mass spectra and fragmentation patterns are examined. The detection limit of the instrument is found to be ~1x108 molecules (350 nm diameter particle) for 2,4-dihydroxybenzoic acid. Version II integrates CO2 laser desorption and tunable VUV ionization in an ion trap and was used for a detailed study of oleyl alcohol, oleic acid and mixtures thereof. Both the degree of fragmentation in the mass spectra and the translational energy of the vaporized molecules are found to vary as a function of desorption energy in the pure particles and as a function of composition in the mixed particles. These changes can be described by the energy absorbed per particle during desorption. We show that these effects hinder the quantitative response of the instrument and have important implications for other two step laser desorption/ionization systems. The final part of this thesis presents preliminary results from atmospherically relevant particles. Mass spectra of cigarette sidestream smoke, fulvic acid, meat cooking, and ammonium bisulfate aerosols are collected using both versions of the instrument. The two step desorption/ionization process only worked for two types of aerosols, while CO2 only mass spectra w.

Book Time of flight Mass Spectrometry

Download or read book Time of flight Mass Spectrometry written by Robert J. Cotter and published by . This book was released on 1997 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the basic principles of time-of-flight (TOF) mass spectrometry with a strong emphasis on applications in biological research. It describes many innovative techniques, including orthogonal extraction, post source decay, and delayed extraction, and surveys ionization techniques used on TOF mass spectrometers such as electron impact, plasma desorption, SIMS, FAB, laser desorption, MALDI, and electrospray. The book features chapters on applications to peptides/proteins, oligonucleotides, and other biological macromolecules, and examines how techniques might be used in sequencing the human genome.

Book Time of Flight Mass Spectrometry and its Applications

Download or read book Time of Flight Mass Spectrometry and its Applications written by E.W. Schlag and published by Newnes. This book was released on 2012-12-02 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: The resurgence of time-of-flight mass spectrometry (TOF-MS) has had its origin in the simplicity of construction and application of such instruments together with the high transmission and the great increase in resolution that has been achieved. The instrument lends itself naturally to a coupling with pulsed laser sources, though this is not a prerequisite. It also affords a time resolution far beyond that traditionally achieved with mass spectrometric rapid scan techniques - a recent example being the real-time analysis of a multi-component mixture from an automobile exhaust. Furthermore, the mass range appears to be extremely large: mass up to 500 kDa and beyond what is being readily measured in the laboratory today. The present set of contributions attempts to give a survey of current applications from many of the active groups in the field. A variety of new applications are considered which are no doubt just the beginning of large new areas of application. By presenting this work in book form it is hoped that it will be of help to the many groups intending to initiate work in this rapidly expanding new area of mass spectrometry.

Book Development of a Portable Aerosol Mass Spectrometer

Download or read book Development of a Portable Aerosol Mass Spectrometer written by Theresa Giáng Vân Evans-Nguỹ̂en and published by . This book was released on 2005 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Aerosol Time of flight Mass Spectrometry  ATOFMS  as a Real time Monitor of Individual Aerosol Particles in Field Studies

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:

Book Advances and Applications of Mass Spectral Techniques for the Characterization of Atmospheric Aerosol Particles

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.

Book The Analysis of Aerosol Time of flight Mass Spectrometry 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:

Book Characterisation and Field Deployment of a Novel Quantitative Time of flight Aerosol Mass Spectrometer  ToF AMS

Download or read book Characterisation and Field Deployment of a Novel Quantitative Time of flight Aerosol Mass Spectrometer ToF AMS written by Silke S. Hings and published by . This book was released on 2007 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book An On line Mass Spectrometer for Aerosols

Download or read book An On line Mass Spectrometer for Aerosols written by Martin Weiss and published by . This book was released on 1997 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: