Journal of Nuclear Science and Technology
Online ISSN : 1881-1248
Print ISSN : 0022-3131
Search
Advanced search
OR
Browse
Search
Volume 4, Issue 9
Displaying 1-5 of 5 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
  • Experimental Analysis of Energy Spectrum Parameters in Slightly Enriched UO2-H2O Lattices
    Setsuo KOBAYASHI, Hiroshi KIKUCHI, Kenichi MATSUOKA
    1967 Volume 4 Issue 9 Pages 451-461
    Published: September 25, 1967
    Released on J-STAGE: April 18, 2008
    DOIhttps://doi.org/10.3327/jnst.4.451
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    The relative neutron temperature represented by the activation ratio (AR) of Lu-Cu, and the modified epithermal index in the form r√Tn/T0(T0=20°C) were measured by foil activation for a wide range of water-to-fuel volume ratios, in slightly enriched UO2-H2O lattices.
    With tight lattices, the values of the activation ratio thus experimentally determined agree better with the two dimensional collision probability calculation than with the one dimensional cylindricalized cell calculation. The values of r√Tn/T0 measured with the use of Au-Mn-Ni alloy foil without Cdfilter are in good agreement with the results calculated by the extended TEMPEST code.
    The neutron temperature Tn and the epithermal index r in a unit cell, derived from the quantities AR and r√Tn/T0, can be expressed respectively by
    Tm=moderator temperature
    from which, it is found that a linear relationship between Tn/Tm and r√Tn/T0 is obtained in the form
    Tn/Tm=1+(1.96±0.048)r√Tn/T0.
    View full abstract
    Download PDF (779K)
  • Measurement of Prompt Neutron Decay Constant in Delayed Critical State of Heavily Reflected Reactor
    Yoshihiko KANEKO, Fujiyoshi AKINO, Ryosuke KUROKAWA, Kenji SUMITA
    1967 Volume 4 Issue 9 Pages 462-467
    Published: September 25, 1967
    Released on J-STAGE: April 18, 2008
    DOIhttps://doi.org/10.3327/jnst.4.462
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    The measurements of αc, the prompt neutron decay constant at delayed critical have been made by pulsed neutron technique in various core configurations of SHE, a graphite-moderated 20% enriched uranium critical assembly. It was confirmed from the results that the value of αc is very strongly dependent on geometrical configurations of the reflector rather than on the atomic ratio of carbon to 285U in the core region. These results are in fairly good agreement with the calculated values obtained directly as the eigenvalue of the characteristic equation on a 34 group P-1 model.
    View full abstract
    Download PDF (458K)
  • Solution of One-Dimensional Group-Diffusion Equation by Laplace Transformation
    Keisuke KOBAYASHI, Hiroshi NISHIHARA
    1967 Volume 4 Issue 9 Pages 468-476
    Published: September 25, 1967
    Released on J-STAGE: April 18, 2008
    DOIhttps://doi.org/10.3327/jnst.4.468
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    A group-diffusion equation for multiregion in one dimension is solved by applying the Laplace transformation and an analytical continuation. Applying the Laplace transformation, a group-diffusion equation is transformed into a system of linear algebraic equations. They are formulated with the use of the transfer matrix adopted in the method by Lie-series. Solutions are given in three different forms, analytical, Taylor's series, and in a form used in the source iteration method.
    View full abstract
    Download PDF (572K)
  • Study on the Rate and the Products of the Reaction between Uranium Monocarbide and Water
    Yoshio HORI, Takashi MUKAIBO
    1967 Volume 4 Issue 9 Pages 477-481
    Published: September 25, 1967
    Released on J-STAGE: April 18, 2008
    DOIhttps://doi.org/10.3327/jnst.4.477
    JOURNAL FREE ACCESS
    Show abstractHide abstract

    The rate of the evolution of gaseous products can be expressed in the form R=const.× θn, where θis the coverage of water on the carbide. The values of n is were found to be 1.0 for CH4, and 0.53 for H2. Those for the C2, C3 and C4 components were 1.0 for the high coverage region and less than unity for those of low coverage. This could be attributed to non-uniformity of the carbide surface.
    View full abstract
    Download PDF (335K)
  • Determination of Hydrogen Fluoride and Uranium(VI) in Crude Uranium Hexafluoride by Hydrolysis and Potentiometric Titration
    Haruka SHINOHARA, Kimie IZAWA, Shigeo TSUJIMURA, Kenji MOTOJIMA
    1967 Volume 4 Issue 9 Pages 482-487
    Published: September 25, 1967
    Released on J-STAGE: April 18, 2008
    DOIhttps://doi.org/10.3327/jnst.4.482
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    A simple method for determining HF and U(VI) in a hydrolyzed solution of UF6 by alkalimetry is described.
    About 1g of UF6 was taken in a polytrifluoromonochloroethylene tube, and hydrolyzed with about 50ml of water in a closed polyethylene bottle. Using a glass electrode, HF in the hydrolyzed solution was titrated potentiometrically with an alkali solution, after the U(VI) had been masked with ammonium sulfate. When the equivalence point for the free acid was reached, hydrogen peroxide was added to the solution and the liberated acid equivalent to U(VI) was titrated with the same standard alkali solution.
    Assuming that the hydrolysis of UF6 takes place stoichiometrically, the accuracy of this method was roughly evaluated to be ±10% for the ratio of HF/UF6 and ±1% for the value of U(VI) in the range of 0 to 1 mole of HF per mole of UF6.
    View full abstract
    Download PDF (423K)
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top