The effect of different oxide additions on the electrical and magnetic properties of copper-manganese ferrites

Summary The electrical and magnetic parameters of copper-manganese ferrites with additions of other metal oxides are compared with those of the 0.15 Cu₂O·0.2 MnO₂·0.5 Fe₂O₃ ferrite without an addition. The magnetic parameters of the ferrites were determined by the method of oscillography of dynamic hysteresis loops. It was established that the introduction of the oxides Bi₂O₃, Sb₂O₃, TiO₂ Cr₂O₃, ZnO, and CaO leads to a substantial improvement of magnetic parameters, while the addition of the oxides BeO, CdO, BaO, Co₂O₂, SrO, and Al₂O₃ causes a deterioration of magnetic properties.     

Determination of the possible duration of performance of a set of tasks

Cybernetics and Systems Analysis -     

Metrological problems in automatic production

Conclusions In order to ensure the successful development and application of automatic systems and, in the first place, high quality for their production, it is necessary to carry out a large amount of metrological work which has not been previously performed by the State Committee's system in working out theoretical foundations and methods of normalizing metrological characteristics of measuring instruments for automatic control, regulating and monitoring systems; in developing methods and equipment for testing and checking measuring devices of automatic system; and in carrying out state testing of automatic measuring systems.The State Committee and its agencies should in future provide metrological evaluations of control, regulation and monitoring systems as a whole.     

Functional features of wind-sensitive receptors triggering the wing muscle neurons of the desert locust, Calliptamus barbarus]

At each side of the head of C. barbarus, 5 receptive fields were found triggering the activity of neurons which directly control the work of wing apparatus. Total number of wind-sensitive receptors (presented by trichoid sensillae) amounts up to 200. Lateral receptive fields 1 and 5 are most developed and contain 24 +/- 5 and 23 +/- 4 sensillae respectively. In the response of a receptor to adequate stimulation, two components may be differentiated--phasic and tonic ones. The discharge frequency of the tonic component is equal to 90--100 impulses per sec. Simultaneous recording of impulse activity in axons of two receptors reveals a possibility of interaction of the receptors. In the experiments performed, this peripheral interaction was of the inhibitory nature. Functional peculiarities of the receptor investigated are discussed.