Journal of Nuclear Science and Technology
Online ISSN : 1881-1248
Print ISSN : 0022-3131
7 巻, 3 号
選択された号の論文の6件中1~6を表示しています
  • Hiroyuki KADOTANI
    1970 年 7 巻 3 号 p. 115-125
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
    Crystal binding effect on the effective resonance integral of UO2 fuel has been evaluated with a simplified phonon frequency distribution. Gaussian frequency distribution having one fitting parameter was adopted. With this distribution the line shape of the resonance cross section was expressed by a superposition of the ψ-functions, which lead to a rather simple calculation of the resonance integral. The calculated results on UO2 crystal showed about 1% increase in the effective resonance integral at room temperature. Although this effect decreased at an elevated temperature, it conversely makes 5 to 10% decrease in Doppler coefficient com-pared with the free gas treatment.
  • Tsutomu NANJYO
    1970 年 7 巻 3 号 p. 126-129
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
    The resonance activation integral of 55Mn was measured relatively to that of 197Au by absolute counting on 56Mn and 198Au: 56Mn was measured with a Ge(Li) counter whose detecting efficiency for γ-rays had been previously determined by a set of IAEA calibrated γ-sources, while 198Au was measured with a 4πβ-γ coincidence counter. The neutron spectrum was deter-mined by P1 calculation and was verified by time-of-fiight method.
    The ratio Il/υ/Ires was obtained experimentallymaking use of boron filters of three different thicknesses.
    The results were Itotal=14.1±0.6 barn and Il/υ/Ires=0.57±0.06,
    for a cutoff energy of 0.63 eV.
  • Satoko TAKAHASHI, Eiji SHIKATA, Hiroshi AMANO
    1970 年 7 巻 3 号 p. 130-136
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
    Some fundamental properties of chromatographic alumina, used for the preparation of radio-isotope generators and for the separation of fission products, were examined in connection with pretreatment procedures prescribed for the alumina to improve its properties in respect of alumina dissolution by certain eluants, its adsorption capacity for certain ions, and the effects of differences in the mode of storage.
    The commercially available brand of chromatographic alumina used in this work showed an increase in its adsorption capacity and a decrease in alumina dissolution, when it was ignited for 10 hr at 400C and treated thereafter with boiling dilute hydrochloric acid. When treated by the above procedure, the properties of the alumina in respect of dissolution and adsorption capacity were found to be unaffected by extended periods of storage under conditions correspond-ing to normal operation.
    The pretreated alumina was made into column form. The dissolution of alumina with vari-ous kinds of eluants and the adsorption capacity for chloride, sulfate, fluoride, tellurite, tellu-rate, and molybdate ions were examined. The dissolution of alumina differed according to eluant, the sequence from larger to smaller dissolution being sodium hydroxide, hydrochloric acid, nitric acid, ammonium hydroxide and sodium chloride. It was also observed that the adsorption capacity and the elution conditions for tellurium and molybdenum were greatly affected by the pH of the solution and their valency.
  • Tsutomu FUKUMOTO, Kenjiro MAEDA, Yoshihiko MATAGI
    1970 年 7 巻 3 号 p. 137-144
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
  • Iwao KOBAYASHI, Shojiro MATSUURA
    1970 年 7 巻 3 号 p. 145-152
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
    For design calculations to determine the local power distribution in a fuel assembly of a power reactor, the neutron flux is usually assumed to be symmetrical at the outer boundary of the assembly. In actuality, experimental data on power distributions are obtained in a finite system where this symmetry does not apply, so that the calculated values cannot be directly compared with observed data. In a zero power critical experiment in particular, the measure-ment must be performed in a fairly small core assembly so economize the amount of fuel materials to be used for simulation. This introduces the necessity of special considerations in the comparison between design and observed data.
    The authors propose a method incorporating direct corrections to the experimentally deter-mined power distributions based on the geometrical buckling of the system. In this method the experimental power P0(r) is divided by the neutron flux Q(r) which is determined in the critical state with geometrical buckling in a bare (one neutron energy group) reactor, neglect-ing the reflector region of the experimental system. A sample application of the method to an actual light water lattice has confirmed the validity of the method.
  • Tatsuzo TONE, Satoru KATSURAGI
    1970 年 7 巻 3 号 p. 153-155
    発行日: 1970/02/25
    公開日: 2008/04/18
    ジャーナル フリー
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