The integral fluxes were used to perform the attenuation relations
of reactor fast neutrons for the investigated concretes as
shown in Fig. 4. Fig. 4 shows that the attenuation properties of reactor fast neutrons for ilmenite–limonite concrete are higher
than that for serpentine concrete which are higher than that for
hematite–serpentine and ordinary concretes. If concrete contains
sufficient moderating and absorbing materials, removal cross section
RR(En) (cm1) will be dominate the attenuation of fast
neutrons.