Download or read book Experiments with Ions and Clusters in a Variable Temperature 22 pole Ion Trap written by Oskar Asvany and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experiments with Ions and Clusters in a Variable Temperature 22 pole Ion Trap written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, 22-pole ion trap machines have been applied to investigate protonated water clusters H+(H2O)n (n=4.10) and ionic hydrocarbons CHn+ (n=2.5) at low temperatures. Protonated water clusters H+(H2O)n play an important role in atmospheric chemistry and in interstellar space. The Taipei 22-pole ion trap machine has been applied to kinetic and spectroscopic investigations of these clusters produced from a supersonic expansion in a corona discharge source. Using low-pressure He buffer gas for collisional thermalization, refrigeration of the ion trap by liquid nitrogen allows a good control of the cluster temperature over the range 80K-350K. This method provides an accurate means of determining the dissociation energies of the cluster ions by measuring their dissociation rates as a function of temperature and calculating their internal energies from vibrational frequencies provided by density functional theory. Results of the thermochemical measurements at well-defined cluster temperatures have been given for H+(H2O)n, n=4.10. The feasibility of using the ion trap to acquire temperature-dependent infrared spectra is presented. The deuteration and abstraction reactions of small ionic hydrocarbons CHn+ (n=2.5) with H2, HD and D2 and the subsequent association processes have been explored at temperatures down to 15K in the Chemnitz 22-pole apparatus. The reactions of the investigated ionic species and their isotopic variants are important for understanding ion-molecule processes in the interstellar medium. One of the starting points of the research program was the question whether protonated methane, CH5+, is subject to H-D-exchange in collisions with HD at low temperatures. It turns out that the rate coefficient for this deuteration process is very small, whereas CH3+ deuterates with HD by three subsequent fast exchange reactions to CD3+ at a temperature of 15K. The latter process is very efficient and happens close to the collision limit. The methane cation,
Download or read book Influence of Internal States on Ion Molecule Reactions in a Temperature Variable 22 Pole Ion Trap written by Sabrina Gärtner and published by Cuvillier Verlag. This book was released on 2014-04-24 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical reactions between ions and neutral gas are very important in the interstellar medium, since they usually have much lower barriers than neutral-neutral reactions. Thus, they are more likely to take place at low temperatures. In this work, the endothermic reactions of CH2D+, H2D+, and N+ with H2 have been investigated in a temperature variable 22-pole ion trap. Under the chosen conditions inside the trap the chemical processes are comparable to those in typical astrophysical environments. At low temperatures, the reactions mentioned above depend very sensitively on the translational and internal energies of the reaction partners. This dependence can be utilized to gain information on the energy levels or the population of the internal states. Based on this sensitivity, two different types of investigations were performed in this work. High resolution spectra of CH2D+ were obtained, resulting in improved predictions for pure rotational transitions. First steps were made towards a detailed understanding of the processes in laser induced reactions, often leading to non-Gaussian line profiles. In addition, the influence of internal states on ion-molecule reactions allowed to determine the purity of para hydrogen samples and yielded insight into the reaction kinetics of the system N+ + H2.
Download or read book Formation of Small Hydrocarbon Ions Under Inter and Circumstellar Conditions written by Igor Savić and published by . This book was released on 2004 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cluster Ions written by Cheuk-Yiu Ng and published by . This book was released on 1993-11-30 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cluster Ions Edited by Cheuk-Yiu Ng, Ames Laboratory, Iowa State University, lowa, USA Tomas Baer, University of North Carolina, NC, USA Ivan Powis, University of Nottingham, UK As a result of many recent advances in both experimental techniques and theoretical methodologies, increasingly detailed and sophisticated studies concerning the formation, structures, energetics, and reaction dynamics of state- or energy-selected molecular ions can now be performed. In order better to serve the ion chemistry and physics communities, each volume of this series will be dedicated to reviewing a specific topic emphasizing new experimental and theoretical developments in the study of ions. This first volume is devoted to the physics and chemistry of clusters. Measurement of cluster ion properties, made as a function of cluster size, are expected to shed some light on the basic understanding of the transition from gas phase to condensed matter. The interest in cluster research is also motivated by the important roles that clusters play in many practical fields, such as catalysis and microelectronics. The authors of the seven chapters making up this volume are among the most active researchers in their respective areas. This series will help stimulate new research directions and point to future opportunities in the field of ion chemistry.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1968 with total page 950 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quadrupole Ion Trap Mass Spectrometry written by Raymond E. March and published by Wiley-Interscience. This book was released on 2005-09-12 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: A definitive reference, completely updated Published in 1989, the First Edition of this book, originally entitled Quadrupole Storage Mass Spectrometry, quickly became the definitive reference in analytical laboratories worldwide. Revised to reflect scientific and technological advances and new applications in the field, the Second Edition includes new chapters covering: * New ion trap instruments of high sensitivity * Peptide analysis by liquid chromatography/ion trap tandem mass spectrometry * Analytical aspects of ion trap mass spectrometry combined with gas chromatography * Simulation of ion trajectories in the ion trap One additional chapter discusses the Rosetta mission, a "comet chaser" that was sent on a ten-year journey in 2004 to study the comet Churyumov-Gerasimenko using, among other instruments, a GC/MS system incorporating a specially designed ion trap mass spectrometer. This comprehensive reference also includes discussions of the history of the quadrupole ion trap, the theory of quadrupole mass spectrometry, the dynamics of ion-trapping chemistry in the quadrupole ion trap, the cylindrical ion trap, miniature traps, and linear ion traps. Complete with conclusions and references, this primer effectively encapsulates the body of knowledge on quadrupole ion trap mass spectrometry. With its concise descriptions of the theory of ion motion and the principles of operation, Quadrupole Ion Trap Mass Spectrometry, Second Edition is ideal for new users of quadrupole devices, as well as for scientists, researchers, and graduate and post-doctoral students working in analytical laboratories.
Download or read book The Diffuse Interstellar Bands written by A.G.G.M. Tielens and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mystery of the diffuse interstellar bands has been variously a curiosity, a co nundrum, and a nuisance for astronomers in the seven decades since the features were first noticed, but recently they have become a forefront issue in astrophysics. Ever since Paul Merrill, in a series of papers starting in 1934, pointed out the interstellar and unidentified nature of the bands, a Who's Who of twentieth century astronomers have tried their hands at solving the problem of identifying the carriers. Henry Norris Russell, Pol Swings, Otto Struve, Paul Ledoux, W. W. Morgan, Walter Adams, Jesse Greenstein, Lawrence Aller, and Gerhard Herzberg all briefly entered the stage, only to move on quickly to other problems where the chances for progress appeared more realistic. In more recent times a number of equally prominent scientists have pursued the bands, but generally only as a sideline to their real astronomical research. But in the past decade, and particularly in the past three years, the view of the search for the diffuse band absorbers as an interesting but perhaps quixotic quest has changed. Today there are several astronomers, as well as laboratory chemists, who are devoting substantial research time and resources to the problem and, as perhaps the most reliable indicator of the newly elevated status of research in this field, some research grants have now been awarded for the study of the bands.
Download or read book Mass Spectrometry written by Jürgen H Gross and published by Springer Science & Business Media. This book was released on 2006-04-05 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mass Spectrometry is an ideal textbook for students and professionals as well as newcomers to the field. Starting from the very first principles of gas-phase ion chemistry and isotopic properties, the textbook takes the reader through the design of mass analyzers and ionization methods all the way to mass spectral interpretation and coupling techniques. Step-by-step, the reader learns how mass spectrometry works and what it can do. The book comprises a balanced mixture of practice-oriented information and theoretical background. It features a clear layout and a wealth of high-quality figures. Exercises and solutions are located on the Springer Global Web.
Download or read book Low Temperatures and Cold Molecules written by Ian W. M. Smith and published by Imperial College Press. This book was released on 2008 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book brings together, for the first time, the results of recent research in areas ranging from the chemistry of cold interstellar clouds (10-20 K), through laboratory studies of the spectroscopy and kinetics of ions, radicals and molecules, to studies of molecules in liquid helium droplets, to attempts to create molecular (as distinct from atomic) Bose-Einstein condensates.
Download or read book Physics of Surfaces and Interfaces written by Harald Ibach and published by Springer Science & Business Media. This book was released on 2006-11-18 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt: This graduate-level textbook covers the major developments in surface sciences of recent decades, from experimental tricks and basic techniques to the latest experimental methods and theoretical understanding. It is unique in its attempt to treat the physics of surfaces, thin films and interfaces, surface chemistry, thermodynamics, statistical physics and the physics of the solid/electrolyte interface in an integral manner, rather than in separate compartments. It is designed as a handbook for the researcher as well as a study-text for graduate students. Written explanations are supported by 350 graphs and illustrations.
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 Electrospray Ionization Mass Spectrometry written by Richard B. Cole and published by Wiley-Interscience. This book was released on 1997-05-06 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive, up-to-date coverage of a revolutionary technique Electrospray ionization mass spectrometry (ESI-MS) has completely changed the way physicists, chemists, and biologists view the study of large molecules. The technique derives detailed information about molecular weights and structures from extremely small sample quantities. ESI-MS can create highly charged forms of very high molecular weight compounds, it is naturally compatible with many types of separation techniques, and it allows noncovalent interactions between molecules in solution to be preserved in the gas phase. But many researchers may not use the technique to its full potential because they are unfamiliar with the different perspectives of its underlying processes, the varied approaches to implementation, and the wide-ranging utility of the technique. In this book, Richard B. Cole and an assemblage of leading researchers present a single-volume compilation of different approaches to the understanding and exploitation of ESI-MS. This comprehensive guide: * Examines the physical and chemical aspects of the electrospray process and describes the events involved in ion formation as well as the electro-chemical phenomena that are central to charged droplet formation during the process * Explores the coupling of electrospray ionization to various mass spectrometers, including quadrupole, magnetic, time-of-flight, quadrupole ion trap, and Fourier transform ion cyclotron resonance instruments * Describes recent progress in interfacing ESI with solution-based separation techniques, including liquid chromatography and capillary electrophoresis * Charts the rapid development of ESI applications and categorizes them by compound type: peptides and proteins, nucleic acids and their constituents, carbohydrates and lipids, small molecules related to pharmacology and drug metabolism, and organometallics and inorganic compounds Electrospray Ionization Mass Spectrometry is the indispensable handbook and reference for anyone who wishes to understand, implement, or apply this technique, including researchers in chemistry, metallochemistry, biochemistry, biology, pharmacology, and physics.
Download or read book Practical Aspects of Trapped Ion Mass Spectrometry Volume IV written by Raymond E. March and published by CRC Press. This book was released on 2010-05-25 with total page 952 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflecting the substantial increase in popularity of quadrupole ion traps and Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometers, Practical Aspects of Trapped Ion Mass Spectrometry, Volume IV: Theory and Instrumentation explores the historical origins of the latest advances in this expanding field. It covers new methods for trapp
Download or read book Mass Spectrometry in Medicinal Chemistry written by Klaus Wanner and published by John Wiley & Sons. This book was released on 2007-06-27 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first overview of mass spectrometry-based pharmaceutical analysis is the key to improved high-throughput drug screening, rational drug design and analysis of multiple ligand-target interactions. The ready reference opens with a general introduction to the use of mass spectrometry in pharmaceutical screening, followed by a detailed description of recently developed analytical systems for use in the pharmaceutical laboratory. Applications range from simple binding assays to complex screens of biological activity and systems containing multiple targets or ligands -- all highly relevant techniques in the early stages in drug discovery, from target characterization to hit and lead finding.
Download or read book Non covalent Interactions written by Pavel Hobza and published by Royal Society of Chemistry. This book was released on 2010 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: Co-authored by an experimentalist (Klaus M3ller-Dethlefs ) and theoretician (Pavel Hobza), the aim of this book is to provide a general introduction into the science behind non-covalent interactions and molecular complexes using some important experimental and theoretical methods and approaches.
Download or read book Quantum Mechanics Volume 1 written by Claude Cohen-Tannoudji and published by John Wiley & Sons. This book was released on 2019-12-04 with total page 950 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of the unrivalled textbook introduces the fundamental concepts of quantum mechanics such as waves, particles and probability before explaining the postulates of quantum mechanics in detail. In the proven didactic manner, the textbook then covers the classical scope of introductory quantum mechanics, namely simple two-level systems, the one-dimensional harmonic oscillator, the quantized angular momentum and particles in a central potential. The entire book has been revised to take into account new developments in quantum mechanics curricula. The textbook retains its typical style also in the new edition: it explains the fundamental concepts in chapters which are elaborated in accompanying complements that provide more detailed discussions, examples and applications. * The quantum mechanics classic in a new edition: written by 1997 Nobel laureate Claude Cohen-Tannoudji and his colleagues Bernard Diu and Franck Laloë * As easily comprehensible as possible: all steps of the physical background and its mathematical representation are spelled out explicitly * Comprehensive: in addition to the fundamentals themselves, the book contains more than 350 worked examples plus exercises Claude Cohen-Tannoudji was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris where he also studied and received his PhD in 1962. In 1973 he became Professor of atomic and molecular physics at the Collège des France. His main research interests were optical pumping, quantum optics and atom-photon interactions. In 1997, Claude Cohen-Tannoudji, together with Steven Chu and William D. Phillips, was awarded the Nobel Prize in Physics for his research on laser cooling and trapping of neutral atoms. Bernard Diu was Professor at the Denis Diderot University (Paris VII). He was engaged in research at the Laboratory of Theoretical Physics and High Energy where his focus was on strong interactions physics and statistical mechanics. Franck Laloë was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris. His first assignment was with the University of Paris VI before he was appointed to the CNRS, the French National Research Center. His research was focused on optical pumping, statistical mechanics of quantum gases, musical acoustics and the foundations of quantum mechanics.
