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The formation of the pseudogap in CeNiSn has been investigated by means of resistivity and specific-heat measurements in high magnetic fields. When the field is raised from 0 to 12 T along the orthorhombic a axis, the semiconductorlike behavior in the resistivity below 6 K disappears and the linear electronic term in the specific heat increases from 57 to 100 mJ/${\mathrm{K}}^{2}$ mol. However, no significant effect was observed for fields along the b and c axes up to 15 T. These results suggest an anisotropic suppression of the pseudogap, which can be interpreted as a result of strong spin polarization of the renormalized narrow band.

The specific heat of Yb 4 As 3 , a mixed-valence system, has been measured down to 100 mK in magnetic fields up to 4 T. at low temperature a nuclear contribution in the specific heat is seen. The Sommerfeld coefficient λ is ∼ 150 mJ/K 2 mole at zero field. The magnetic field opens up a gap at low temperatures.

Specific heat measurements were carried out down to 80 mK in magnetic fields up to 8 T on Sm3Te4. Two sharp antiferromagnetic phase transitions were observed at 0.7 and 0.9 K. At 1.4 K, the specific heat shows a broad peak which can be fitted by the impurity Kondo model for S = 1 2 . Heavy-fermion character at low temperature was established with a large γ-value, 0.6 J/K2 mol Sm3+.