Magnetic transient birefringence of ferrofluids : particle size determination
نویسندگان
چکیده
Relaxation time measurements of magnetically induced birefringence of ferrofluid solutions are performed with samples of various polydispersities. dH, the hydrodynamic diameter of particles deduced from experiments, is compared to a numerical computation with a log-normal distribution. Dynamic magnetic birefringence appears to be a good test of the tail of the sample size distribution. For a narrow distribution (03C3 ~ 0.25), the experiment is in good agreement with the model: dH is two times larger than the most probable diameter and corresponds to the largest particles in the sample. J. Physique 48 (1987) 1385-1391 AOÚT 1987,
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