Download or read book The Deactivation of HF v written by J. F. Bott and published by . This book was released on 1985 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water is often present as an impurity in HF chemical laser systems and can affect laser performance because of the large HF(1) - H2O deactivation rate coefficient. Diatomic molecules have been found to deactivate the higher vibrational levels of HF(v) with rate coefficients that scale with v as v superscript n where n = 2.7 when the deactivation process is exothermic. This scaling does not hold for HF(v) - H2 collisions in which the primary deactivation process is an endothermic V-V transfer with the endothermicity increasing with v. The room temperature (T = 295 K) deactivation rate of HF (v = 3) by H2O has been measured to be faster than the deactivation rate of HF(v = 1) by H2O by a factor of 3.9. On the basis of a previously reported measurement of the HF(v = 1) - H2O rate coefficient, the deactivation rate coefficient of HF(v = 3) by H2O is estimated to be 16 microseconds/Torr, which is a factor of 3 faster than the hard sphere collision rate. The theoretical implication of this fast-rate coefficient are reviewed. Keywords: Chemical kinetics; Vibrational deactivation.
Download or read book The Deactivation of Vibrationally Excited Hydrogen Fluoride by Reactive Atoms written by Gerard Paul Quigley and published by . This book was released on 1975 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow Tube Studies of the Deactivation of HF V by Selected Polyatomic Molecules written by Munson A. Kwok and published by . This book was released on 1975 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: A large-diameter, medium-pressure flow tube has been used to study deactivation processes by selected polyatomic molecules that are potentially relevant in chemical laser systems. Effective vibrational deactivation rate constants for HF(v = 1,2,3) relaxed by H2S, CO2, N2O, CH4, CF4, and SF6 have been determined. The rates for a given chaperone increase with increasing v. The agreement with results for HF(1) + M reported from laser-induced fluorescence experiments is generally very good. The role of HF rotational energy in absorbing a vibrational energy defect is examined. An empirical correlation with adjusted vibrational energy defect is suggested.
Download or read book Deactivation of HF v written by S. J. Arnold and published by . This book was released on 1977 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: A discharge-flow-tube technique has been used to measure the deactivation of HF(v=1,2). Effective vibrational deactivation rate constants for HF(v=1,2) relaxed by C2H4, C2H3F, 1 1C2H2F2, cis 1 2C2H2F2, trans 1 2C2H2F2, C2HF3, and C2F4 have been determined.
Download or read book Gas Kinetics and Energy Transfer written by P G Ashmore and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Specialist Periodical Reports provide systematic and detailed review coverage of progress in the major areas of chemical research. Written by experts in their specialist fields the series creates a unique service for the active research chemist, supplying regular critical in-depth accounts of progress in particular areas of chemistry. For over 80 years the Royal Society of Chemistry and its predecessor, the Chemical Society, have been publishing reports charting developments in chemistry, which originally took the form of Annual Reports. However, by 1967 the whole spectrum of chemistry could no longer be contained within one volume and the series Specialist Periodical Reports was born. The Annual Reports themselves still existed but were divided into two, and subsequently three, volumes covering Inorganic, Organic and Physical Chemistry. For more general coverage of the highlights in chemistry they remain a 'must'. Since that time the SPR series has altered according to the fluctuating degree of activity in various fields of chemistry. Some titles have remained unchanged, while others have altered their emphasis along with their titles; some have been combined under a new name whereas others have had to be discontinued. The current list of Specialist Periodical Reports can be seen on the inside flap of this volume.
Download or read book Vibrational Deactivation of HF v written by R. F Heidner (III.) and published by . This book was released on 1975 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: The deactivation of HF(v = 1) and DF(v = 1) by H and D atoms was studied at 295 K by means of the techniques of laser-induced infrared fluoresence and isothermal calorimetry. The upper limits for the deduced rate coefficients are well-defined, but the lower limits are imprecise. The results of this study are compared with other experimental data and with trajectory calculations. Qualitative data are presented regarding the role of reactive, i.e., F-atom exchange, versus nonreactive collisions in the removal of the v = 1 level. A verification of the method was made by determining a rate coefficient for H + HCl(v = 1) that is in good agreement with a recent study.
Download or read book NBS Special Publication written by and published by . This book was released on 1979 with total page 810 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deactivation of Higher Vibrational Levels of HF by F Atoms written by J. F. Bott and published by . This book was released on 1984 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The vibrational relaxation times of HF(v = 3) and HF(V = 1) in the presence of F atoms have been measured in a slow-flow fluorescence cell at room temperature. The HF is pumped to vibrational levels v = 1, 2, and 3 by a pulsed HF laser. It was found that F atoms deactivate HF(V = 3) faster than they do HF(v = 1) by a factor of 20.8 + or - 2.0. This dependence of the deactivation rate coefficient on v agrees with that determined for the exothermic V-V or V-R, T deactivation of HF(V = 1 to 3) by N2, O2, D2 and HC1. (Author).
Download or read book The Vibrational Deactivation of HF v written by Jerry F. Bott and published by . This book was released on 1977 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rate of HF(v = 2 and 3) removal by H atoms was measured at T = 295 K. The measurements were performed by laser-induced fluorescence in a discharge flow tube in which H atoms were produced by a microwave discharge. The absolute H-atom concentrations were measured by isothermal calorimetry with a Pt wire coil as a catalytic probe. A small fraction of the injected HF(v = 0) was pumped first to HF(v = 1) and subsequently to HF(v = 2) and HF(v = 3) by the multiline output from a pulsed HF transverse excitation atmospheric (TEA) laser.
Download or read book The 12th Informal Conference on Photochemistry National Bureau of Standards Gaithersburg Maryland June 28 July 1 1976 written by and published by . This book was released on 1976 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976-06 with total page 1216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1986 with total page 992 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas Lasers written by Masamori Endo and published by CRC Press. This book was released on 2018-10-03 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lasers with a gaseous active medium offer high flexibility, wide tunability, and advantages in cost, beam quality, and power scalability. Gas lasers have tended to become overshadowed by the recent popularity and proliferation of semiconductor lasers. As a result of this shift in focus, details on modern developments in gas lasers are difficult to find. In addition, different types of gas lasers have unique properties that are not well-described in other references. Collecting expert contributions from authorities dealing with specific types of lasers, Gas Lasers examines the fundamentals, current research, and applications of this important class of laser. It is important to understand all types of lasers, from solid-state to gaseous, before making a decision for any application. This book fills in the gaps by discussing the definition and properties of gaseous media along with its fluid dynamics, electric excitation circuits, and optical resonators. From this foundation, the discussion launches into the basic physics, characteristics, applications, and current research efforts for specific types of gas lasers: CO lasers, CO2 lasers, HF/DF lasers, excimer lasers, iodine lasers, and metal vapor lasers. The final chapter discusses miscellaneous lasers not covered in the previous chapters. Collecting hard-to-find material into a single, convenient source, Gas Lasers offers an encyclopedic survey that helps you approach new applications with a more complete inventory of laser options.
Download or read book Free Radicals in Chemistry and Biology written by Milan Lazar and published by CRC Press. This book was released on 1989-03-31 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elementary radical reactions are described in terms of fundamental knowledge of organic chemistry and chemical physics in this valuable reference text. The complex radical processes of nonchain and chain mechanisms, such as dimerization, alkylation, polymerization, telomerization, halogenation pyrolysis, oxidation and combustion, are complemented by reactions in chemical lasers and in the cosmos, as well as by reactions in biological objects under normal or pathological metabolism. The text also provides the synthesis of facts from various fields of research and involves mechanisms where free radicals appear either as main or side intermediates in one of the several alternatives of the reaction pathway. Highlights include 38 tables and 39 figures.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1986 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reaction Dynamics written by I. Smith and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last 30 years our knowledge and understanding of molecular processes has followed the development of increasingly sophisticated tech niques for studying fast reactions. Although the results are reported in papers and reviews, it is sometimes difficult for those not themselves active in these fields to find their way through the mass of published material. We hope that each book in this series will present a clear account of the present state of knowledge in a particular field of physical chemistry to research workers in related fields, to research students, and for the preparation of undergraduate and post-graduate lectures. Each chapter describes the theoretical develop ment of one area of study and the appropriate experimental techniques; the results presented are chosen to illustrate the theory rather than to attempt a comprehensive review. The first volume published in 1972 was concerned with the reactions of small molecules and free radicals in the gas phase. The development of flash photolysis in the 1950s paved the way by making it possible to generate free radicals in sufficient concentration for a spectroscopic" snapshot" to reveal their molecular structure. Their role in kinetic systems could then be followed directly, rather than be inferred from mechanism. The shock tube enabled gas mixtures to be heated to any desired temperature in a time which was shorter than subsequent chemical reactions. Discharge-flow methods enabled the reactions of atoms and free radicals to be studied directly.
Download or read book Quantum Electronics written by and published by Academic Press. This book was released on 1979-11-15 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum Electronics
