Photoionization Type Patents (Class 250/423P)
  • Patent number: 4038549
    Abstract: In a technique for isotope enrichment a system for selectively exciting increased amounts of one isotope type in an environment of plural isotope types by the application of excitation energy at a plurality of frequencies which selectively excite the one isotope from its ground energy level and one or more typically low-lying excited levels.
    Type: Grant
    Filed: June 8, 1973
    Date of Patent: July 26, 1977
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Sargent Janes, Richard H. Levy
  • Patent number: 4035638
    Abstract: A process for the separation of one isotope from a mixture of isotopes and an apparatus for carrying out said process. The process comprises generating a beam of the atoms or molecules, introducing the beam into a laser cavity in such manner that the direction of the laser beam is substantially perpendicular to the direction of motion of the beam, irradiating the beam with a radiation adapted to being about the excitation only of the isotopic species to be separated, reflecting the laser beam back and forth between at least a pair of opposed sides of the laser cavity, such as between two mirrors opposite and parallel to each other which are located on these sides, for deflecting the desired isotopic species, and collecting said species.
    Type: Grant
    Filed: March 28, 1975
    Date of Patent: July 12, 1977
    Inventors: Abraham Szoke, Isaiah Nebenzahl
  • Patent number: 4031389
    Abstract: The isotope U.sup.235 is separated from a gasified isotope mixture of U.sup.235 and U.sup.238 by selectively exciting the U.sup.235 from the ground state utilizing resonant absorption of radiation from precisely tuned lasers. The excited isotope is then selectively ionized by electron bombardment. It then is separated from the remaining isotope mixture by electromagnetic separation.
    Type: Grant
    Filed: June 26, 1974
    Date of Patent: June 21, 1977
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Gary R. Russell, Che Jen Chen, Kenneth G. Harstad
  • Patent number: 4031397
    Abstract: A process and apparatus for separating isotopes from gaseous mixtures by forming a seeded molecular beam comprising a carrier gas and the isotopes, exposing the seeded beam to a laser light having a particular radiation frequency to accentuate differences in the velocity profiles of the isotopes in the beam and separating the isotopes based upon the differences in their velocity profiles. The frequency of the laser is such as to excite only one of the isotopes, e.g. the lighter one, so that it possesses a larger amount of rotational energy without exciting the other isotope(s).
    Type: Grant
    Filed: August 25, 1975
    Date of Patent: June 21, 1977
    Assignee: Massachusetts Institute of Technology
    Inventor: Mark J. Cardillo
  • Patent number: 4025790
    Abstract: In a procedure for selectively separating the isotopes of a multi-isotopic element by forming a gas of isotopic compounds of the element, selectively exciting the molecules of one isotopic compound by application of laser radiation thereto, and separating the excited molecules from the other components of the gas by physical or chemical means, the efficiency of the separation is improved by passing the gas, prior to laser excitation, through a nozzle to cause it to undergo adiabatic expansion to form an undercooled gas stream, and applying the laser radiation to the gas stream.
    Type: Grant
    Filed: December 11, 1975
    Date of Patent: May 24, 1977
    Assignee: URANIT Uran-Isotopentrennungs-GmbH
    Inventors: Heinz Leonhard Jetter, Karl Gurs, Wolfgang Englisch
  • Patent number: 4025408
    Abstract: A method for deuterium enrichment by the infrared-induced addition reaction of a deuterium halide with an unsaturated aliphatic compound. A gaseous mixture of a hydrogen halide feedstock and an unsaturated aliphatic compound, particularly an olefin, is irradiated to selectively vibrationally excite the deuterium halide contained therein. The excited deuterium halide preferentially reacts with the unsaturated aliphatic compound to produce a deuterated addition product which is removed from the reaction mixture.
    Type: Grant
    Filed: May 28, 1976
    Date of Patent: May 24, 1977
    Assignee: The United States of America as represented by the United States Energy Research and Development Administration
    Inventor: John B. Marling
  • Patent number: 4024399
    Abstract: A probe for detecting the evaporation rate of an electron beam evaporation source and for monitoring induced ionization of the vapor. A negatively biased electrode responds to ions in the vapor to measure the ion current density. The ions measured may result from the process of vaporization or from laser produced isotopically selective ionization. The probe provides a current output which is detected as an indication of vaporization or laser ionization rate.
    Type: Grant
    Filed: January 6, 1975
    Date of Patent: May 17, 1977
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George S. Janes, Leonard N. Litzenberger
  • Patent number: 4024217
    Abstract: A method for separating specific isotopes present in an isotopic mixture by aerodynamically accelerating a gaseous compound to form a jet of molecules, and passing the jet through a stream of electron donor atoms whereby an electron transfer takes place, thus forming negative ions of the molecules. The molecular ions are then passed through a radiofrequency quadrupole mass filter to separate the specific isotopes. This method may be used for any compounds having a sufficiently high electron affinity to permit negative ion formation, and is especially useful for the separation of plutonium and uranium isotopes.
    Type: Grant
    Filed: May 23, 1975
    Date of Patent: May 17, 1977
    Assignee: The United States of America as represented by the United States Energy Research and Development Administration
    Inventors: Sol Wexler, Charles E. Young
  • Patent number: 4023038
    Abstract: A system employing multiple, upper excitation levels in a technique for isotopically selective ionization to improve the ionization efficiency. In a technique which employs laser radiation to excite particles with isotopic selectivity, excitation is produced to a plurality of excited states below the ionization level with the result of increasing the number of available excited particles for ionization and thereby increasing the ionization cross-section for improved system efficiency.
    Type: Grant
    Filed: September 19, 1974
    Date of Patent: May 10, 1977
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Sargent Janes, Charles T. Pike
  • Patent number: 4020350
    Abstract: The isotopes of a gas are separated by using a circularly polarized laser to excite a lower energy level to higher split intermediate energy levels, a second laser pulse of the same circular polarization is applied to said energized gas at a time .pi./.DELTA..omega. where .pi..DELTA. is the frequency splitting of the intermediate levels, to excite said excited intermediate levels to a higher energy level where an ionizing field ionizes the atoms or molecules in the higher level so that they may be separated from the un-ionized atoms or molecules of the other isotope.
    Type: Grant
    Filed: June 23, 1975
    Date of Patent: April 26, 1977
    Assignee: Massachusetts Institute of Technology
    Inventor: Theodore W. Ducas
  • Patent number: 4009391
    Abstract: Frequency selective means, particularly for use in uranium enrichment by laser induced isotopically selective ionization to suppress unwanted lasing of the excited uranium medium. The frequency selective means, such as filters, are placed at intervals in a column of laser illuminated uranium vapor and are transmissive to the illuminating laser frequencies but nontransmissive to frequencies at which population inversions exist in the excited uranium. The filters limit the path length and correspondingly the gain in the excited uranium to prevent high intensity lasing by the uranium itself.
    Type: Grant
    Filed: June 25, 1974
    Date of Patent: February 22, 1977
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Sargent Janes, Richard H. Levy, Lawrence A. Levin
  • Patent number: 4001582
    Abstract: In an apparatus for local surface analysis of a target sample in which an ion probe is directed to the target for sputtering particles. A chamber having walls heated to a high temperature (above 2200.degree. K as a rule) collects sputtered particles. The particles entering the chamber are subjected to successive adsorptions and desorptions before they leave the chamber for entry into a mass spectrometer. Scanning may be provided as in conventional SIMS systems.
    Type: Grant
    Filed: June 20, 1975
    Date of Patent: January 4, 1977
    Assignee: Agence Nationale de Valorisation de la Recherche (ANVAR)
    Inventors: Raimond Castaing, Guy Blaise, Roger Quettier
  • Patent number: 4000420
    Abstract: Isotope separation is achieved between species A and B having an absorption resonance separated by an isotopic shift by selectively exciting a portion of species A using a tunable photon source of narrow emission line with and subsequently causing collisions with an optically excited third species to selectively ionize the excited portion of species A. When ionized, species A is easily separated by any technique, using its ionized condition to distinguish it from species B.
    Type: Grant
    Filed: June 11, 1974
    Date of Patent: December 28, 1976
    Assignee: The Board of Trustees of Leland Stanford Junior University
    Inventor: Stephen E. Harris
  • Patent number: 4000423
    Abstract: An electron beam vapor source for use in laser enrichment of uranium and providing fast response intermittent vaporization to permit interruption of the enrichment process without wasting vapor or requiring long term reheating.
    Type: Grant
    Filed: December 5, 1974
    Date of Patent: December 28, 1976
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Sargent Janes, Leonard N. Litzenberger, Donald F. Twombly
  • Patent number: 4000421
    Abstract: In uranium enrichment, an electrode structure of thin, tensioned, parallel wires for use in applying an electric field to a region of a flowing uranium plasma including selectively ionized particles in order to accelerate the ionized particles for separate collection without interfering with the motion of neutral particles.
    Type: Grant
    Filed: September 30, 1974
    Date of Patent: December 28, 1976
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Sargent Janes, John Philip Dotson
  • Patent number: 3996469
    Abstract: A floating mass or matrix for use in the melt of an electron beam vapor source to permit a wide latitude of evaporant level without necessary replenishment while at the same time reducing convective currents in the melt.
    Type: Grant
    Filed: January 6, 1975
    Date of Patent: December 7, 1976
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventor: George Sargent Janes
  • Patent number: 3996470
    Abstract: Method and apparatus for separating isotope types by inducing an isotopically selective vibrational excitation of molecules containing at least one atom of the element type whose isotopes are to be separated. Vibrational excitation is induced in the molecules by finely tuned, narrow bandwidth laser radiation applied to a gaseous flow of the molecules. Isotopic separation of the molecules is achieved from the enhanced difference in diffusion rates for the molecules due to an alteration of the accommodation coefficients in the excited molecules.
    Type: Grant
    Filed: October 15, 1974
    Date of Patent: December 7, 1976
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventor: James C. Keck
  • Patent number: 3992625
    Abstract: Method and apparatus for separating selectively ionized particles from a plasma of moving particles by application of a magnetic field gradient in a direction to which the ionized particles are to be accelerated for collection. By creating conditions of adiabatic particle motion for charged particles in the magnetic field, the selectively ionized particles will be induced to follow the magnetic field lines in the direction of weaker field strength. The direction of this gradient is made different from the general direction of particle motion to permit extraction of the ions from the plasma. The extracted ions deposit on a collection surface in enriched proportions.
    Type: Grant
    Filed: December 27, 1973
    Date of Patent: November 16, 1976
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventors: George Schmidt, Gerald M. Halpern, William R. L. Thomas