Pulsed NMR measurements of the susceptibility and the transverse and longitudinal relaxation times of 3 He intermixed with 9 nm of carbon particles have been performed down to 0.4 mK. The results indicate that the first atomic layer has an antiferromagnetic exchange interaction. The intermediate solid-liquid region, ~ 5 atomic layers thick, favors ferromagnetism and approaches a ferromagnetic transition at the lowest temperatures.

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The viscosity r 1 of liquid 3He has been measured along the melting curve from 1 to 100 mK by means of a vibrating wire viscometer. In the normal Fermiliquid region we find 1/rl T2 = 1.17-3.10T, where ~l is in I~P and T in K. At the transition temperature T a = 2.6 mK a rapid decrease occurs in tln, the viscosity of the normal component. Within 0.3 mK below T A, qn decreases to about 25 ~o of rlA , but then becomes essentially constant. In the B phase rlnfirst decreases to 20 % of q A and then seems to increase below 1.4 inK. Data on p,, the density of the normal component, are also presented in the A and B phases. The results show that viscous flow is accompanied by a flow of zero dissipation, thus proving superfluidity in the A and B phases. The viscosity data at magnetic fields up to 0.9T have been related to theoretical calculations of the energy gap of superfluid 3He near T a . The splitting of the A transition and the suppression of the B phase in an external field were also measured.

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