Download or read book Isotope Separation by Selective Unimolecular Photoisomerization written by Stanford University. Microwave Laboratory and published by . This book was released on 1974 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Separation of Isotopes of Biogenic Elements in Two phase Systems written by Boris Mikhailovich Andreev and published by Elsevier. This book was released on 2006-12-01 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: Separation of Isotopes of Biogenic Elements provides a detailed overview of this area of research covering all aspects from the value of isotope effects to their practical use (equilibrium single-stage isotope effect - kinetics and mass transfer – multiplication of the single-stage isotope separation factor - technological peculiarity of processes) with the purpose of extraction from the natural mixture of the enriched and highly concentrated isotopes. In contrast to traditional books on the theory of isotope separation, the theoretical part of the book describes separation in two-phase processes in counter-flow columns. The experimental part of the book presents systematic analysis of specialists in the field of isotope separation in counter-flow columns. This book will be of interest to scientists, engineers and technical workers engaged in isotope separation processes and isotope application in nuclear physics, medicine, agro-chemistry, biology and other areas. This book may also be used in teaching theory and practical aspects in courses on physical chemistry and Isotope separation of light elements by physicochemical methods. * summarises current state of isotope research, especially biogenic elements* covering all aspects from the value of isotope effects to their practical use* of interest to scientists, engineers and technical workers engaged in isotope separation processes and isotope application
Download or read book Laser Isotope Separation by Selective Excited State Photochemistry Progress Report June 1 1975 February 29 1976 written by and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress has been made on the development of a low-temperature source for the generation of uranium atoms, and the use of laser-induced predissociation in Rb2* for isotope separation. However, our main efforts have concentrated on understanding and improving the laser isotope separation of 35Cl and 37Cl by photochemical means. The gas-phase reaction ICl* with 1,2-dibromoethylene produces both cis-1-bromo-2-chloroethylene and cis-1,2-dichloroethylene stereospecifically. Selective excitation of I37Cl with a tunable cw dye laser causes identical degrees of isotope enrichment in both products. By the use of an I35Cl cell placed inside the cavity of the dye laser, the 35Cl:37Cl ratio may be changed from 3:1 (natural abundance) to greater than 1:15. A competing pathway, cis-trans isomerization of starting material, also occurs and is the fastest reaction. The stereospecificity of the reaction and the relative rate of geometrical isomerization to substitution are the same when chlorine atoms, formed by the photodissociation of ICl or Cl2, are scavenged by dibromoethylene. We conclude that, kinetically, ICl* acts as a free chlorine atom. That isotope separation is achieved by a free-radical scavenging mechanism is indeed remarkable and owes its success to the structure of the scavenger and the choice of initial conditions.
Download or read book Isotope Separation and Isotope Exchange written by and published by . This book was released on 1953 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Exchange as a Versatile Isotope Separation Process written by G. H. Clewett and published by . This book was released on 1950 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Isotope Separation in Atomic Vapor written by Petr Artemovich Bokhan and published by John Wiley & Sons. This book was released on 2006-12-13 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by leading Russian scientists, including Nobel laureate, A.M. Prokhorov (1916-2002), this first book on this important technology allows an understanding of the physics of atomic vapor laser isotope separation and new photochemical methods of laser isotope separation. One entire chapter is devoted to chemical reactions of atoms in excited states, while further chapters deal with the separation of isotopes by one photon isotope-selective and coherent isotope-selective two photon excitation of atoms. A final chapter looks at the prospects for the industrial production of isotope products by laser isotope separation. The whole is rounded off by six appendices.
Download or read book Laser Isotope Separation by Selective Excited State Photochemistry Annual Progress Report March 31 1976 February 28 1977 written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results are presented providing insight into the mechanisms of photochemical separation of Cd isotopes by selective excitation of ICl in the presence of halogenated olefins. The types of scrambling reactions that can be expected in isotope separation by scavenging are discussed along with strategies for minimizing such reactions. The experimental results are summarized and the reaction mechanisms are represented by graphic equations. (JRD).
Download or read book Isotope Separation written by Stelio Villani and published by . This book was released on 1976 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Theory of Isotope Separation as Applied to the Large Scale Production of U235 written by Karl Cohen and published by . This book was released on 2015-03-07 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotope separation is the process of concentrating specific isotopes of a chemical element by removing other isotopes. The use of the nuclides produced is various. The largest variety is used in research (e.g. in chemistry where atoms of "marker" nuclide are used to figure out reaction mechanisms). By tonnage, separating natural uranium into enriched uranium and depleted uranium is the largest application. In the following text, mainly the uranium enrichment is considered. This process is a crucial one in the manufacture of uranium fuel for nuclear power stations, and is also required for the creation of uranium based nuclear weapons. Plutonium-based weapons use plutonium produced in a nuclear reactor, which must be operated in such a way as to produce plutonium already of suitable isotopic mix or grade. While different chemical elements can be purified through chemical processes, isotopes of the same element have nearly identical chemical properties, which makes this type of separation impractical, except for separation of deuterium. There are three types of isotope separation techniques: Those based directly on the atomic weight of the isotope. Those based on the small differences in chemical reaction rates produced by different atomic weights. Those based on properties not directly connected to atomic weight, such as nuclear resonances. The third type of separation is still experimental; practical separation techniques all depend in some way on the atomic mass. It is therefore generally easier to separate isotopes with a larger relative mass difference. For example deuterium has twice the mass of ordinary (light) hydrogen and it is generally easier to purify it than to separate uranium-235 from the more common uranium-238. On the other extreme, separation of fissile plutonium-239 from the common impurity plutonium-240, while desirable in that it would allow the creation of gun-type nuclear weapons from plutonium, is generally agreed to be impractical.
Download or read book Isotope Separation by Selective Dissociative Electron Attachment Final Technical Report written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A description of work performed on isotopically selective, photo-enhanced production of SF−5 from SF6 is included. The primary task under the present contract was the construction of a second-generation experimental apparatus for the study of the simultaneous interaction of electrons, photons, and molecules. The collinear electron and laser beam arrangement employed previously has been retained, but a new electron gun design has been adopted which avoids the troublesome interaction of the laser beam with the electron gun filament. The system has been designed for maximum compatibility with aggressive gases such as UF6. Details of the design and construction of this system are given. Proposals for future work include work on SF6 and UF6.
Download or read book The Separation of Uranium Isotopes written by P. Caldirola and published by . This book was released on 1962 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optics Communications written by and published by . This book was released on 1974-09 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Diffusion distillation Process for the Separation of Isotopes written by J. H. Atkins and published by . This book was released on 1954 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Isotope Separation by Photoselective Dissociative Electron Capture written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A method of separating isotopes based on photoselective electron capture dissociation of molecules having an electron capture cross section dependence on the vibrational state of the molecule. A molecular isotope source material is irradiated to selectively excite those molecules containing a desired isotope to a predetermined vibrational state having associated therewith an electron capture energy region substantially non-overlapping with the electron capture energy ranges associated with the lowest vibration states of the molecules. The isotope source is also subjected to electrons having an energy corresponding to the non-overlapping electron capture region whereby the selectively excited molecules preferentially capture electrons and dissociate into negative ions and neutrals. The desired isotope may be in the negative ion product or in the neutral product depending upon the mechanism of dissociation of the particular isotope source used. The dissociation product enriched in the desired isotope is then separated from the reaction system by conventional means. Specifically, .sup. 235 UF.sub. 6 is separated from a UF.sub. 6 mixture by selective excitation followed by dissociative electron capture into .sup. 235 UF.sub. 5 - and F.
Download or read book Chemical Problems in Stable Isotope Separation written by Arthur J. Miller and published by . This book was released on 1947 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetically Activated and Guided Isotope Separation written by Thomas R. Mazur and published by Springer. This book was released on 2015-11-19 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes a proof-of-principle experiment demonstrating a technique for stable isotope enrichment called Magnetically Activated and Guided Isotope Separation (MAGIS). Over the past century many enriched isotopes have become available, thanks largely to electromagnetic separators called calutrons. Due to substantial maintenance and operating costs, the United States decommissioned the last of its calutrons in 1998, leading to demand for alternative methods of isotope separation. The work presented here suggests the promise for MAGIS as a viable alternative to the calutrons. The MAGIS technique combines optical pumping with a scalable magnetic field gradient to enrich atoms of a specific isotope in an atomic beam. Benchmarking this work against the calutron using lithium as a test case, the author demonstrated comparable enrichment in a manner that should scale to the production of similar quantities, while requiring vastly less energy input.
Download or read book Isotope Effects in Chemical Processes written by William Spindel and published by . This book was released on 1969 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
