Abstract: A chemical sensitive field effect transistor transducer is provided having a semipermeable membrane on the surface of a chemical selective system overlying an insulated gate field effect transistor. Such a field effect transistor transducer is effective for the measurement of chemical constituents of factory waste water containing micro-particles, saliva or blood containing proteins, etc., where conventional devices give unreliable results.

Abstract: A reference electrode of an insulated gate field effect transistor having the surface of the gate region thereof coated with a hydrophobic organic polymer membrane. Since this reference electrode is much smaller in size than conventional reference electrodes, an integrated measurement system can easily be constructed by using this reference electrode. This measurement system is especially effective for measuring various ions in the living body.

Abstract: Permanent magnet composites comprising a cured liquid polymer matrix and hard magnetic ferrite particles dispersed therein are disclosed. The magnetic ferrite particles are present in an amount within the range of from about 5 to about 14 parts per part of polymer matrix, the magnetic ferrite particles having a general formula MO.n Fe.sub.2 O.sub.3, wherein M is selected from the group consisting of barium, strontium, lead, and mixtures thereof, and n has a value in the range of from about 4.5 to about 6.2. Various additives may optionally be employed to improve compatibility of the matrix polymer with the ferrite particles and to improve processibility. Also disclosed is a method for producing such magnetic composites.