The d.c. electrical conductivity of sodium vanadate, potassium vanadate, lithium vanadate and their solid solutions sodium-potassium vanadate, sodium-lithium vanadate were measured by a two-probe method in the temperature range covering their transition points. These materials show sharp change in conductivity at their phase transition temperatures. In sodium, potassium and lithium vanadates an exponential increase in d.c. conductivity is observed in ferroelectric region while discontinuities are observed above the transition temperatures. The activation energy in paraelectric state of the solid solutions is found to be higher than in ferroelectric state. In solid solutions the activation energy depends upon sodium vanadate concentration.

Pyroelectric properties of poled solid solutions of lead-barium titanate and leadstrontium titanate have been investigated in the temperature range covering their transition points. The values of pyroelectric current and coefficients of (Pb,-Ba~_x)TiO~ and (Pb.~-Sr~ _~)TiO3lx =0"8-0-5) show a sharp peak at the Curie temperature. It is observed that these values change with Ba or Sr concentration in the respective solid solutions.

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