
Medical Applications of 14 MeV Neutrons
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moderator, small articial diamond particles (abbreviated as diamond) whose
density is supposed to be 3.2 g/cm
3
were studied instead. e change of the
ratio of the fast neutron ux to the neutron ux in the tumor, RFNT, with the
thickness of the moderator is shown in Figure 9.2. e results from Figure 9.2
are as follows:
1. Neither polythene nor water, composed of carbon, hydrogen, and oxygen,
can be used as a neutron moderator in BNCT. e TNACSs of carbon,
hydrogen, and oxygen are about 3mb, 0.19 b, and 0.1mb, respectively. In
water and polythene, the number densities of hydrogen atoms are high, ...