Download or read book UV Spectroscopic Probing of the Reaction Kinetics of Criegee Intermediates CH2OO and the Syn and Anti Isomers of CH3CHOO written by and published by . This book was released on 2014 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Direct Spectroscopic and Kinetic Studies of the Simplest Criegee Intermediate written by Elizabeth Stack Foreman and published by . This book was released on 2017 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric chemistry is driven largely by free radical species whose reactions determine both the composition and oxidative capacity of the atmosphere. Carbonyl oxides, or Criegee Intermediates, formed in the ozonolysis of alkenes in the troposphere are highly reactive biradicals/zwitterions that are implicated in the production of secondary organic aerosol and particulate matter. This thesis will focus on the following aspects of the spectroscopy and kinetics related to the simplest Criegee Intermediate, formaldehyde oxide: (1) kinetics of IO radical formation from the CH2I + O2 reaction, (2) spectroscopy and dynamics of electronically excited states of CH 2OO, (3) the kinetics of reactions of CH2OO with trace atmospheric pollutants. The spectroscopic and kinetic study of IO radicals formed as minor products in the laboratory synthesis of Criegee Intermediates is performed using cavity ring-down spectroscopy (CRDS). We observe experimentally that IO radicals exhibit vibrational state specific formation kinetics and suggest that this is due to a product branching ratio controlled by the degree of internal excitation in the reactants. IO and CH2OO are produced simultaneously in the reaction of CH2I with O2 and exhibit overlapping absorption bands in the near-ultraviolet/visible. This poses a challenge for direct detection of CH2OO using a linear absorption technique. The measured rate constant for the formation of IO is used to deconvolute the total observed absorption spectrum into individual molecular components. Both CRDS and single-pass broadband transient absorption spectroscopy (BBTAS) are used to independently measure the absolute absorption cross sections for the second electronically excited state of CH2OO in the near-ultraviolet/visible. We show that the absorption spectra do not exhibit fine structure, even at the lowest excitation energies, and that the observed broad lineshapes cannot be attributed hot bands. This suggests that the photolysis quantum yield is “1 and the observed structure in the electronic absorption spectrum, that is absent from the action spectrum, is the result of relaxation via nonradiative population transfer to a long-lived state or fluorescence. BBTAS is subsequently used to probe the kinetics of the reactions of CH2OO with two inorganic acids: HCl and HNO3. We find that these reactions occur at or near the collision limit and that nitric acid in particular may be locally competitive with water vapor, which is widely accepted as the dominant sink for Criegee Intermediates in the atmosphere. Taken together these studies provide a deeper understanding of the role Criegee Intermediates play in tropospheric chemistry.
Download or read book Reactivity of Criegee Intermediates CH2OO and CH3CHOO written by and published by . This book was released on 2013 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics of Criegee Intermediate Reactions with Nitric Acid Measured by UV Absorption Spectroscopy written by 楊絜甯 and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetic Studies of Small Criegee Intermediates by UV Absorption Spectroscopy written by 趙彣 and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectroscopy and Kinetics written by James S. Mattson and published by Marcel Dekker. This book was released on 1973 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Oxygen in Chemistry written by Christopher S. Foote and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: Taking an interdisciplinary approach, this book and its counterpart, Active Oxygen in Biochemistry, explore the active research area of the chemistry and biochemistry of oxygen. Complementary but independent, the two volumes integrate subject areas including medicine, biology, chemistry, engineering, and environmental studies.
Download or read book Mechanisms of Atmospheric Oxidation of the Alkanes written by Jack G Calvert and published by Oxford University Press. This book was released on 2008-09-15 with total page 1005 pages. Available in PDF, EPUB and Kindle. Book excerpt: An international team of eminent atmospheric scientists have prepared Mechanisms of Atmospheric Oxidation of the Alkanes as an authoritative source of information on the role of alkanes in the chemistry of the atmosphere. The book includes the properties of the alkanes and haloalkanes, as well as a comprehensive review and evaluation of the existing literature on the atmospheric chemistry of the alkanes and their major atmospheric oxidation products, and the various approaches now used to model the alkane atmospheric chemistry. Comprehensive coverage is given of both the unsubstituted alkanes and the many haloalkanes. All the existing quality measurements of the rate coefficients for the reactions of OH, Cl, O(3P), NO3, and O3 with the alkanes, the haloalkanes, and their major oxidation products have been reviewed and evaluated. The expert authors then give recommendations of the most reliable kinetic data. They also review the extensive literature on the mechanisms and rates and modes of photodecomposition of the haloalkanes and the products of atmospheric oxidation of the alkanes and the haloalkanes, and make recommendations for future use by atmospheric scientists. The evaluations presented allow an extrapolation of the existing kinetic and photochemical data to those alkanes and haloalkanes that are as yet unstudied. The current book should be of special interest and value to the modelers of atmospheric chemistry as a useful input for development of realistic modules designed to simulate the atmospheric chemistry of the alkanes, their major oxidation products, and their influence on ozone and other trace gases within the troposphere.
Download or read book Atmospheric Chemistry and Physics written by John H. Seinfeld and published by John Wiley & Sons. This book was released on 2012-12-18 with total page 1249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly restructured and updated with new findings and new features The Second Edition of this internationally acclaimed text presents the latest developments in atmospheric science. It continues to be the premier text for both a rigorous and a complete treatment of the chemistry of the atmosphere, covering such pivotal topics as: * Chemistry of the stratosphere and troposphere * Formation, growth, dynamics, and properties of aerosols * Meteorology of air pollution * Transport, diffusion, and removal of species in the atmosphere * Formation and chemistry of clouds * Interaction of atmospheric chemistry and climate * Radiative and climatic effects of gases and particles * Formulation of mathematical chemical/transport models of the atmosphere All chapters develop results based on fundamental principles, enabling the reader to build a solid understanding of the science underlying atmospheric processes. Among the new material are three new chapters: Atmospheric Radiation and Photochemistry, General Circulation of the Atmosphere, and Global Cycles. In addition, the chapters Stratospheric Chemistry, Tropospheric Chemistry, and Organic Atmospheric Aerosols have been rewritten to reflect the latest findings. Readers familiar with the First Edition will discover a text with new structures and new features that greatly aid learning. Many examples are set off in the text to help readers work through the application of concepts. Advanced material has been moved to appendices. Finally, many new problems, coded by degree of difficulty, have been added. A solutions manual is available. Thoroughly updated and restructured, the Second Edition of Atmospheric Chemistry and Physics is an ideal textbook for upper-level undergraduate and graduate students, as well as a reference for researchers in environmental engineering, meteorology, chemistry, and the atmospheric sciences. Click here to Download the Solutions Manual for Academic Adopters: http://www.wiley.com/WileyCDA/Section/id-292291.html
Download or read book Organic Reaction Mechanisms 2015 written by A. C. Knipe and published by John Wiley & Sons. This book was released on 2019-02-08 with total page 717 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic Reaction Mechanisms 2015, the 51st annual volume in this highly successful and unique series, surveys research on organic reaction mechanisms described in the available literature dated 2015. The following classes of organic reaction mechanisms are comprehensively reviewed: Reaction of Aldehydes and Ketones and their Derivatives Reactions of Carboxylic, Phosphoric, and Sulfonic Acids and their Derivatives Oxidation and Reduction Carbenes and Nitrenes Nucleophilic Aromatic Substitution Electrophilic Aromatic Substitution Carbocations Nucleophilic Aliphatic Substitution Carbanions and Electrophilic Aliphatic Substitution Elimination Reactions Polar Addition Reactions Cycloaddition Reactions Molecular Rearrangements An experienced team of authors compile these reviews every year, so that the reader can rely on a continuing quality of selection and presentation.
Download or read book The Future of Atmospheric Chemistry Research written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2017-01-29 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our world is changing at an accelerating rate. The global human population has grown from 6.1 billion to 7.1 billion in the last 15 years and is projected to reach 11.2 billion by the end of the century. The distribution of humans across the globe has also shifted, with more than 50 percent of the global population now living in urban areas, compared to 29 percent in 1950. Along with these trends, increasing energy demands, expanding industrial activities, and intensification of agricultural activities worldwide have in turn led to changes in emissions that have altered the composition of the atmosphere. These changes have led to major challenges for society, including deleterious impacts on climate, human and ecosystem health. Climate change is one of the greatest environmental challenges facing society today. Air pollution is a major threat to human health, as one out of eight deaths globally is caused by air pollution. And, future food production and global food security are vulnerable to both global change and air pollution. Atmospheric chemistry research is a key part of understanding and responding to these challenges. The Future of Atmospheric Chemistry Research: Remembering Yesterday, Understanding Today, Anticipating Tomorrow summarizes the rationale and need for supporting a comprehensive U.S. research program in atmospheric chemistry; comments on the broad trends in laboratory, field, satellite, and modeling studies of atmospheric chemistry; determines the priority areas of research for advancing the basic science of atmospheric chemistry; and identifies the highest priority needs for improvements in the research infrastructure to address those priority research topics. This report describes the scientific advances over the past decade in six core areas of atmospheric chemistry: emissions, chemical transformation, oxidants, atmospheric dynamics and circulation, aerosol particles and clouds, and biogeochemical cycles and deposition. This material was developed for the NSF's Atmospheric Chemistry Program; however, the findings will be of interest to other agencies and programs that support atmospheric chemistry research.
Download or read book Computational Molecular Spectroscopy written by Per Jensen and published by John Wiley & Sons. This book was released on 2000-11-02 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the use of modern computational methods in predicting high resolution molecular spectra, which allows the experimental spectroscopist to interpret and assign real spectra. * Offers a comprehensive treatment of modern computation techniques. * Provides a collection of material from different areas of theoretical chemistry and physics. * Bridges the gap between traditional quantum chemistry and experimental molecular spectroscopy.
Download or read book Chiral Analysis written by Kenneth W. Busch and published by Elsevier. This book was released on 2011-10-13 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chiral Analysis covers an important area of analytical chemistry of relevance to a wide variety of scientific professionals. The target audience is scientific professionals with an undergraduate background in chemistry or a related discipline, specifically organic chemists, researchers in drug discovery, pharmaceutical researchers involved with process analysis or combinatorial libraries, and graduate students in chemistry. Chapters have been written with the nonspecialist in mind so as to be self-contained.* Broad coverage - spectroscopic and separation methods covered in a single volume* Up-to-date and detailed review of the various techniques available and/or under development in this field* Contributions from leading experts in the field
Download or read book Advances in Chemical Engineering written by John H Seinfeld and published by Academic Press. This book was released on 1992-02-03 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Chemical Engineering
Download or read book Air Pollution Modeling and its Application XXIV written by Douw G. Steyn and published by Springer. This book was released on 2016-02-10 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current developments in air pollution modelling are explored as a series of contributions from researchers at the forefront of their field. This newest contribution on air pollution modelling and its application is focused on local, urban, regional and intercontinental modelling; data assimilation and air quality forecasting; model assessment and evaluation; aerosol transformation. Additionally, this work also examines the relationship between air quality and human health and the effects of climate change on air quality. The work is comprised of selected papers presented at the 34th International Technical Meeting on Air Pollution Modelling and its Application held in Montpellier, France in 2015. The book is intended as reference material for students and professors interested in air pollution modelling at the graduate level as well as researchers and professionals involved in developing and utilizing air pollution models.
Download or read book Physical Chemistry of Gas Liquid Interfaces written by Jennifer A. Faust and published by Elsevier. This book was released on 2018-06-04 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physical Chemistry of Gas-Liquid Interfaces, the first volume in the Developments in Physical & Theoretical Chemistry series, addresses the physical chemistry of gas transport and reactions across liquid surfaces. Gas-liquid interfaces are all around us, especially within atmospheric systems such as sea spry aerosols, cloud droplets, and the surface of the ocean. Because the reaction environment at liquid surfaces is completely unlike bulk gas or bulk liquid, chemists must readjust their conceptual framework when entering this field. This book provides the necessary background in thermodynamics and computational and experimental techniques for scientists to obtain a thorough understanding of the physical chemistry of liquid surfaces in complex, real-world environments.
Download or read book Chemistry of the Upper and Lower Atmosphere written by Barbara J. Finlayson-Pitts and published by Elsevier. This book was released on 1999-11-17 with total page 993 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here is the most comprehensive and up-to-date treatment of one of the hottest areas of chemical research. The treatment of fundamental kinetics and photochemistry will be highly useful to chemistry students and their instructors at the graduate level, as well as postdoctoral fellows entering this new, exciting, and well-funded field with a Ph.D. in a related discipline (e.g., analytical, organic, or physical chemistry, chemical physics, etc.). Chemistry of the Upper and Lower Atmosphere provides postgraduate researchers and teachers with a uniquely detailed, comprehensive, and authoritative resource. The text bridges the "gap" between the fundamental chemistry of the earth's atmosphere and "real world" examples of its application to the development of sound scientific risk assessments and associated risk management control strategies for both tropospheric and stratospheric pollutants. - Serves as a graduate textbook and "must have" reference for all atmospheric scientists - Provides more than 5000 references to the literature through the end of 1998 - Presents tables of new actinic flux data for the troposphere and stratospher (0-40km) - Summarizes kinetic and photochemical date for the troposphere and stratosphere - Features problems at the end of most chapters to enhance the book's use in teaching - Includes applications of the OZIPR box model with comprehensive chemistry for student use
