Light scattering determination of magnetic moments of magnetotactic bacteria (invited)
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چکیده
where a = ~H/kBT, kB i~ Boltzmann's constant, T is te~ perature, and ~ is def1ned as before. The total stat1c structure factor S(QL,QR,a) is therefore the single nilrticle structllre factor, \~eighted by th" angular dis tribution function, integrated over all angles: S(QL,QR,a) = Nf p(~,a) Ssp(QL,QR,~) d~ (3) Light scattering was used to determine both ~he. average length8 and magnetic moment of the bact~r1a 1n cultures Sl and 52. Since the volume of Fe304 1S only about 1/1000 of the volume of.a bacterium, we a~sume the scattering strength is un1form over the ent1re bacterium. Thus, modeling the bacteria as optically isotropic cylinders of length L and radius R, one can show that the single particle static structure factor is given by
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