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The effective resonance absorption integral for 238U, _~, in a uranium-graphite lattice, : described in[1] was measured. The value I~= (10.3 * 0.3)b was obtained. The dependences of ~, P28 and (~2c8)/(cr~5 } on the ratio of the volumes of graphite and uranium, VC/V U = 38; 76; 152 and on the thmkness of the wat6r space around the uranium rods for VC/Vu ~ 38 were investigated. The measurements were made by means of an activation procedure with the utilization of a Ge(Li) -spectrometer for recording y-radiation from 239Np with an energy of 277 keV and the fission product 143Ce with an energy of 293 keV. The results of the measurements are presented in Tables 1 and 2. For convenience, the values of the parameters are normalized to the corresponding values in a "dry" lattice for Vc/V U = 38. Their analysis allow one to draw the following conclusions.1. The observed dependence of I~ on the ratio V C/V U agrees well with the theoretical data and is explaLued by the departure of the spectrum of epicadmium neutrons incident on a uranium rod from a 1/rE distribution.2. The introduction of a water space around the uranium rods with a thickness up to 6 mm does not affect the quantity ~.(ff28)//ff25x and are not reduced with an increase in the ratio V C/V U 3. The values of the quantities ~. c ~ f / 028 in the lattice and the thickness of the water space around the uranium rods, which is explained by moderation of the neutron spectrum.4. With an increase in the thickness of the water space around the uranium rods, the ratio (~Cs)/(a~ and the parameter P29 are reduced most rapidly for small space thicknesses.

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