Download or read book Collisional Transfer Between Excited Electronic States as a Mechanism for Sulfur Mass independent Fractionation written by Alexander William Hull and published by . This book was released on 2020 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Great Oxygenation Event, the introduction of O2 into the Earth’s atmosphere approximately 2.5 billion years ago, is a critical milestone in the development of life on Earth. The exact timing of this event is thought to be correlated with the disappearance of Archean sulfur isotopic anomalies, called Sulfur Mass -Independent Fractionation (S-MIF), in the rock record. This anomalous fractionation pattern can be described, generally, as an enrichment in the three rare isotopes: S-33 (0.75%), S-34 (4.25%) S-36 (0.01%), relative to the most abundant isotopologue S-32 (0.75%), However, the mechanism for the generation of S-MIF in a reducing atmosphere is still unknown. I use the B-X UV transition (~31,000−36,000 cm−1) in S2 as a proxy for study of excited state collisional transfer as a possible mechanism for S-MIF. The short-lifetime B state (natural lifetime: 32 ns) state-mixes extensively with a longer-lifetime B” state (4200 ns). Furthermore, the most abundant isotopologue of S2, 32S-32S has only half the number of rotational states compared to its asymmetric counterparts. In this work, I replicated Green and Western’s effective Hamiltonian for the X, B, and B” states with additional considerations for mass-dependent vibrational level shifts and nuclear permutation effects. I hypothesize that the collisional transfer between the B and B" states occurs differently for different isotopologues. This difference results in a different average excited state lifetimes, which, in turn, affects the relative rate at which they undergo chemical reactions and enter the rock record. Here, spectroscopic B/B” perturbations act as doorways through which population can exchange between the B and B” states. My model incorporates absorption, fluorescence, and predissociation, as described by Green and Western. It also includes the Gelbart-Freed model for electronically inelastic collisions and Brunner and Pritchard model for rotationally inelastic collisions. I calculate the amount of each isotopologue that enters the rock record by time-dependently solving a master equation kinetic model. Results show that, generally, each region where a B vibronic state crosses a B" vibronic state behaves differently. However, the interactions display some systematic behavior. Because of the energy level patterns, lighter isotopologues are generally favored over the heavier ones (i.e. 32-36
Download or read book Aquatic Organic Matter Fluorescence written by Paula G. Coble and published by Cambridge University Press. This book was released on 2014-07-14 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: A core text on principles, laboratory/field methodologies, and data interpretation for fluorescence applications in aquatic science, for advanced students and researchers.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 1398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling of Atmospheric Chemistry written by Guy P. Brasseur and published by Cambridge University Press. This book was released on 2017-06-19 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical modeling of atmospheric composition is a formidable scientific and computational challenge. This comprehensive presentation of the modeling methods used in atmospheric chemistry focuses on both theory and practice, from the fundamental principles behind models, through to their applications in interpreting observations. An encyclopaedic coverage of methods used in atmospheric modeling, including their advantages and disadvantages, makes this a one-stop resource with a large scope. Particular emphasis is given to the mathematical formulation of chemical, radiative, and aerosol processes; advection and turbulent transport; emission and deposition processes; as well as major chapters on model evaluation and inverse modeling. The modeling of atmospheric chemistry is an intrinsically interdisciplinary endeavour, bringing together meteorology, radiative transfer, physical chemistry and biogeochemistry, making the book of value to a broad readership. Introductory chapters and a review of the relevant mathematics make this book instantly accessible to graduate students and researchers in the atmospheric sciences.
Download or read book Atmospheric Evolution on Inhabited and Lifeless Worlds written by David C. Catling and published by Cambridge University Press. This book was released on 2017-04-13 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive and authoritative text on the formation and evolution of planetary atmospheres, for graduate-level students and researchers.
Download or read book Mass Spectrometry written by Edmond de Hoffmann and published by Wiley. This book was released on 2001-10-10 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offers a complete overview of the principles, theories and key applications of modern mass spectrometry in this introductory textbook. Following on from the highly successful first edition, this edition is extensively updated including new techniques and applications. All instrumental aspects of mass spectrometry are clearly and concisely described; sources, analysers and detectors. * Revised and updated * Numerous examples and illustrations are combined with a series of exercises to help encourage student understanding * Includes biological applications, which have been significantly expanded and updated * Also includes coverage of ESI and MALDI
Download or read book Earth s Early Atmosphere and Surface Environment written by George H. Shaw and published by Geological Society of America. This book was released on 2014 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nothing provided
Download or read book Comets II written by M. Festou and published by University of Arizona Press. This book was released on 2004-11 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of comets is a field that has seen tremendous advances in recent years, far surpassing the knowledge reflected in the original Comets volume published as part of the Space Science Series in 1982. This new volume, with more than seventy contributing authors, represents the first complete overview of comet science in more than a decade and contains the most extensive collection of knowledge yet assembled in the field. Comets II situates comet science in the global context of astrophysics for the first time by beginning with a series of chapters that describe the connection between stars and planets. It continues with a presentation of the formation and evolution of planetary systems, enabling the reader to clearly see the key role played in our own solar system by the icy planetesimals that were the seeds of the giant planets and transneptunian objects. The book presents the key results obtained during the 1990s, in particular those collected during the apparition of the exceptional comets C/Hyakutake and C/Hale-Bopp in 1996-1997. The latest results obtained from the in situ exploration of comets P/Borrelly and P/Wild 2 are also discussed in detail. Each topic of is designed to be accessible to students or young researchers looking for basic, yet detailed, complete and accurate, information on comet science. With its emphasis on the origin of theories and the future of research, Comets II will enable scientists to make connections across disciplinary boundaries and will set the stage for discovery and new understanding in the coming years.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1987 with total page 1014 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics and Chemistry of the Solar System written by John S. Lewis and published by Academic Press. This book was released on 2013-10-22 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physics and Chemistry of the Solar System is a broad survey of the Solar System. The book discusses the general properties and environment of our planetary system, including the astronomical perspective, the general description of the solar system and of the sun and the solar nebula). The text also describes the solar system beyond mars, including the major planets; pluto and the icy satellites of the outer planets; the comets and meteors; and the meteorites and asteroids. The inner solar system, including the airless rocky bodies; mars, venus, and earth; and planets and life about other stars, is also encompassed. Mathematicians, chemists, physicists, geologists, astronomers, meteorologists, and biologists will find the book useful.
Download or read book Evolution of Early Earth s Atmosphere Hydrosphere and Biosphere written by Stephen E. Kesler and published by Geological Society of America. This book was released on 2006-01-01 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The history of Earth's early atmosphere, hydrosphere, and biosphere, from Hadean through Proterozoic time, is one of geology's enduring puzzles. Ore deposits provide important insights into this history because they contain elements and minerals that are highly sensitive to the geochemical environment in which they form. Just what these minerals tell us remains a matter of considerable debate, however. When and how did life develop, an oxygen-rich atmosphere form, and sulfate dominate the ocean? This volume contains reports on these questions from both sides of the aisle for iron and manganese formations, uranium paleoplacers and hydrothermal deposits, and exhalative sulfides and oxides."--Publisher's website.
Download or read book Enzymes written by Robert A. Copeland and published by John Wiley & Sons. This book was released on 2004-04-07 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fully updated and expanded-a solid foundation for understandingexperimental enzymology. This practical, up-to-date survey is designed for a broadspectrum of biological and chemical scientists who are beginning todelve into modern enzymology. Enzymes, Second Editionexplains the structural complexities of proteins and enzymes andthe mechanisms by which enzymes perform their catalytic functions.The book provides illustrative examples from the contemporaryliterature to guide the reader through concepts and data analysisprocedures. Clear, well-written descriptions simplify the complexmathematical treatment of enzyme kinetic data, and numerouscitations at the end of each chapter enable the reader to accessthe primary literature and more in-depth treatments of specifictopics. This Second Edition of Enzymes: A Practical Introductionto Structure, Mechanism, and Data Analysis features refinedand expanded coverage of many concepts, while retaining theintroductory nature of the book. Important new featuresinclude: A new chapter on protein-ligand binding equilibria Expanded coverage of chemical mechanisms in enzyme catalysisand experimental measurements of enzyme activity Updated and refined discussions of enzyme inhibitors andmultiple substrate reactions Coverage of current practical applications to the study ofenzymology Supplemented with appendices providing contact information forsuppliers of reagents and equipment for enzyme studies, as well asa survey of useful Internet sites and computer software forenzymatic data analysis, Enzymes, Second Edition isthe ultimate practical guide for scientists and students inbiochemical, pharmaceutical, biotechnical, medicinal, andagricultural/food-related research.
Download or read book The Atmosphere and Climate of Mars written by Robert M. Haberle and published by Cambridge University Press. This book was released on 2017-06-29 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Humanity has long been fascinated by the planet Mars. Was its climate ever conducive to life? What is the atmosphere like today and why did it change so dramatically over time? Eleven spacecraft have successfully flown to Mars since the Viking mission of the 1970s and early 1980s. These orbiters, landers and rovers have generated vast amounts of data that now span a Martian decade (roughly eighteen years). This new volume brings together the many new ideas about the atmosphere and climate system that have emerged, including the complex interplay of the volatile and dust cycles, the atmosphere-surface interactions that connect them over time, and the diversity of the planet's environment and its complex history. Including tutorials and explanations of complicated ideas, students, researchers and non-specialists alike are able to use this resource to gain a thorough and up-to-date understanding of this most Earth-like of planetary neighbours.
Download or read book Spectroscopy and Photochemistry of Planetary Atmospheres and Ionospheres written by Vladimir A. Krasnopolsky and published by Cambridge University Press. This book was released on 2019-02-14 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews the fundamentals for studying chemical compositions of planetary atmospheres and ionospheres, for graduate students and researchers.
Download or read book Volcanism in Antarctica 200 Million Years of Subduction Rifting and Continental Break up written by J.L. Smellie and published by Geological Society of London. This book was released on 2021-06-09 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: This memoir is the first to review all of Antarctica’s volcanism between 200 million years ago and the Present. The region is still volcanically active. The volume is an amalgamation of in-depth syntheses, which are presented within distinctly different tectonic settings. Each is described in terms of (1) the volcanology and eruptive palaeoenvironments; (2) petrology and origin of magma; and (3) active volcanism, including tephrochronology. Important volcanic episodes include: astonishingly voluminous mafic and felsic volcanic deposits associated with the Jurassic break-up of Gondwana; the construction and progressive demise of a major Jurassic to Present continental arc, including back-arc alkaline basalts and volcanism in a young ensialic marginal basin; Miocene to Pleistocene mafic volcanism associated with post-subduction slab-window formation; numerous Neogene alkaline volcanoes, including the massive Erebus volcano and its persistent phonolitic lava lake, that are widely distributed within and adjacent to one of the world’s major zones of lithospheric extension (the West Antarctic Rift System); and very young ultrapotassic volcanism erupted subglacially and forming a world-wide type example (Gaussberg).
Download or read book Remote Compositional Analysis written by Janice L. Bishop and published by Cambridge University Press. This book was released on 2019-11-28 with total page 655 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive overview of the spectroscopic, mineralogical, and geochemical techniques used in planetary remote sensing.
Download or read book Molecular Mechanisms of Photosynthesis written by Robert E. Blankenship and published by John Wiley & Sons. This book was released on 2014-05-05 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the clear writing and accessible approach that have made it the authoritative introduction to the field of molecular photosynthesis, this fully revised and updated edition now offers students and researchers cutting-edge topical coverage of bioenergy applications and artificial photosynthesis; advances in biochemical and genetic methods; as well as new analytical techniques. Chapters cover the origins and evolution of photosynthesis; carbon metabolism; photosynthetic organisms and organelles; and the basic principles of photosynthetic energy storage. The book's website includes downloadable PowerPoint slides.
