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EBR-2 Fisson-Product-Source Test No. 1

Description: A fission-product source (FPS) was irradiated in EBR-II to provide data for calibrating the facility's fuel-element rupture detector (FERD), which is a delayed-neutron monitor, and germanium-lithium argon-scanning system (GLASS), a fission-gas-activity monitor. A metal alloy source, Ni-3.2 wt.% uranium, provided quantitative recoil release of the fission-product nuclides. The source alloy, in tubular form, was irradiated as core-region segments of 18 capsules in the FPS subassembly. The irradiation showed that the response of the FERD was linear with increasing reactor power. The magnitude of the FERD signal was dependent on local fission rate for the FPS and the flow path of the sodium carrying the delayed-neutron emitters. The relatively high fission-gas activity released by the FPS allowed accurate calibration of the GLASS under several modes of operation and provided data for verifying a gas-release model for the reactor.
Date: August 1978
Creator: Strain, R. V.; Fogle, G. L.; Thresh, H. R.; Heinrich, R. R.; Freyer, R. M.; So, B. Y. C. et al.
Partner: UNT Libraries Government Documents Department

Report on the Possible Effects on the Surrounding Population of an Assumed Release of Fission Products into the Atmosphere from a 300 Megawatt Nuclear Reactor Located at Lagoona Beach, Michigan

Description: Report issued by the APDA over studies conducted on the release of radioactive particles near Lagoona Beach, Michigan in 1955. "The possible effects on the surrounding population of a release of fission products at the Lagoona Beach site" (p. 1) are discussed. This report includes tables, maps, and illustrations.
Date: July 1957
Creator: Gomberg, H. J.; Bassett, Thomas; Velez, Carlos & Donnell, Alton P.
Partner: UNT Libraries Government Documents Department

A SURVEY AND EVALUATION OF U$sup 233$ FISSION YIELD DATA

Description: A survey of the pertinent literature was made to ascertain the status of data on U/sup 233/ fission-product yields. The various experimental determinations were evaluated, and the most recent mass-spectrometric results were used as a basis for deriving a set of preferred yields. These yields were compared with values reported in two other recent compilations, and for yields >1%, the three setrs agreed with each other to an average precision of <5%. It was concluded that recent measurements have somewhar improved the reliability of U/sup 233/ fission yield data, but some recommendations for additional experimental work were made (auth)
Date: July 13, 1962
Creator: Ferguson, R.L. & O'Kelley, G.D.
Partner: UNT Libraries Government Documents Department

The Decontamination of Uranium from Fission Products by the Use of the Uranyl Oxalate Precipitation Reaction

Description: Abstract: "Decontamination factors of the order of 10-4 were obtained for Beta and Gamma emitters present as fission products when uranium was precipitated from 50 mC activity level solutions as uranyl oxalate under normal uranium yield conditions for three cycles (~60%). Factors of the order of 10-3 were obtained by the use of this reaction with similar solutions under relatively high uranium yield conditions for three cycles (~90%). The uranium peroxide precipitation reaction proved to be of no value on such solutions, yielding decontamination factors of only 17.1 Beta emitters and 1.2 for Gamma emitters for three cycles."
Date: May 10, 1951
Creator: Kelchner, B. L.
Partner: UNT Libraries Government Documents Department

Estimation of Fission Product Beta Activity in Uranium Containing U-237 and UX

Description: Abstract: "It has been found that a mixture of acetone and ethyl ether containing nitric acid will wash uranium and 98 per cent of its natural daughters from a celluloss pulp column. Eight per cent of a "fission product" spike also comes through in this fraction but may be reduced by suitable modifications. A second development with two molar hydrochloric acid washes out 83 per cent of the original spike activities, and an additional three per cent is obtained by extruding the column, ashing, and counting the ash. A tentative procedure is given and recoveries tabulated."
Date: 1951
Creator: Meinhard, J. E.
Partner: UNT Libraries Government Documents Department

High Energy Fission and Spallation of Uranium

Description: From introduction: "This report is an attempt to examine, semiquantitavely, the way the competition between neutron emission and fission varies for heavy nuclei as a function of nuclear type and excitation energy. Many of the ideas herein are the results of discussions with R. H. Goeckermann and W. Heckrotte of the University of California Radiation Laboratory."
Date: February 25, 1954
Creator: Batzel, Roger Elwood
Partner: UNT Libraries Government Documents Department

The Fission Neutron Spectrum of 25

Description: Abstract: "Photographic plates have been used to measure the energy of neutrons from the fission of 25. The spectrum as inferred from the ranges of 850 protons recoiling in the forward direction shows a very wide maximum at ~1.5 Mev with an exponentially decreasing high energy tail which extends beyond 7 Mev. The minimum energy neutrons recorded were ~700 kv. If the spectrum is extrapolated to zero, one finds that this average neutron energy is about 1.85 Mev. The stopping power of the plates was calibrated by the use of monochromatic neutrons from the Li-7(pn) Be-7 reaction and the d-d reaction."
Date: February 11, 1944
Creator: Richards, Hugh T. & Perlman, Isadore
Partner: UNT Libraries Government Documents Department

An Influence Function for the Beta Activity of Uranium(235) Fission Products

Description: Abstract: "Computations have been made of the total beta activity of the fission products arising from the slow neutron fission of U-235. A curve is given exhibiting the activity the activity per unit fission, for time intervals after fission ranging from 0.01 second to 10 years. This influence function is compared with some published experimental data and with the statistical curve of Way and Wigner. A curve facilitates estimation of the activity in the particular case where the fission rate has been constant throughout a known time interval. Finally, an influence function for the particular group of fission products consisting of complete and partial chains having volatile first members is given. This report is based on studies conducted for the Atomic Energy Commission under Contract AT-11-1-GEN-8."
Date: September 1, 1950
Creator: Thornton, J. Kendall. & Houghton, William J.
Partner: UNT Libraries Government Documents Department

Introduction to Diffusion Theory and to Pile-Theory

Description: The following report describes and foretells the situation in medium in which neutrons are being (a)produced as fast neutrons, (b) slowed down to thermal speeds by impacts with nuclei, and (c) absorbed by nuclei in such a manner that sometimes fresh fast neutrons appear at the place where a thermal neutron has just appeared.
Date: October 5, 1944
Creator: Darrow, Karl K.
Partner: UNT Libraries Government Documents Department

Identification of Reaction Products Formed During Magnesium Reduction of Uranium Tetrafluoride: Report

Description: Abstract: "This report describes the results of X-ray diffraction examination of reaction products from a series of experiments performed by Mallinckrodt Chemical Works as an acid in understanding the process of bomb reduction of UF4. UF4 is initially reduced to UF3 by magnesium at 560 C., and subsequently to metal at 600 C. MgF2 from the initial reaction forms a coating on the magnesium which retards the final spontaneous reaction."
Date: May 15, 1953
Creator: Schwartz, C. M. & Vaughan, D. A.
Partner: UNT Libraries Government Documents Department

Identification and Characterization of Shielded Isotopes in Uranium Fission

Description: Abstract: "The first shielded isotope, 34th Br-82 has been isolated in fission. Its fission yield is about 3 x 10-(-5)%. This is a direct measurement of the yield of a primary fission product and gives direct information as to the distribution of nuclear charge among primary fission fragments of given mass numbers as discussed by Glendenin and Coryell."
Date: November 27, 1946
Creator: Feldman, Milton H.
Partner: UNT Libraries Government Documents Department

Numerical Technique for Criticality Calculations on Hydrogen Moderated Reactors

Description: "The purpose of this memo is to set down a derivation and numerical technique for a method that can be used for criticality calculations on bare reactors containing hydrogen together with another moderator such as BeO. The method and notation are that of G. Goertzel (NDA)-1, and D. Selengut (NEPA). In the interest of the computers, the numerical technique, associated notation, and calculation form are modeled after that currently used by the ANP Physics Group for BeO moderated reactors."
Date: August 20, 1951
Creator: Webster, J. W.
Partner: UNT Libraries Government Documents Department

Some Comments on the Mechanism of Fission

Description: A correlation of spontaneous fission rates with Z and A is made to show that these rates depend on the nuclear type. Some suggestions as to the mechanisms are given and it is also shown how these relate to the mechanism of slow neutron and photo fission.
Date: July 25, 1951
Creator: Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department

Microscopic Calculation of Fission Fragment Energies for the 239Pu(nth,f) Reaction

Description: We calculate the total kinetic and excitation energies of fragments produced in the thermal-induced fission of {sup 239}Pu. This result is a proof-of-principle demonstration for a microscopic approach to the calculation of fission-fragment observables for applied data needs. In addition, the calculations highlight the application of a fully quantum mechanical description of scission, and the importance of exploring scission configurations as a function of the moments of the fragments, rather than through global constraints on the moments of the fissioning nucleus. Using a static microscopic calculation of configurations at and near scission, we have identified fission fragments for the {sup 239}Pu (n{sub th}, f) reaction and extracted their total kinetic and excitation energies. Comparison with data shows very good overall agreement between theory and experiment. Beyond their success as a proof of principle, these calculations also highlight the importance of local constraints on the fragments themselves in microscopic calculations.
Date: October 3, 2011
Creator: Younes, W & Gogny, D
Partner: UNT Libraries Government Documents Department