The phenomenon of ferrimagnetic spin-wave resonance [uncompensated antiferromagnetic spin-wave resonance] has been detected for the first time. It has been observed in carbon nanotubes, produced by high-energy ion beam modification of diamond single crystals in aOE (c) 100 > direction. Peculiarities of spin-wave resonance observed allow to insist on the formation in given nanotubes of s (+)-superconductivity at room temperature, coexisting with uncompensated antiferromagnetic ordering.