No abstract available

No abstract available

[en] Various types of time-variant filters are considered and compared with time-invariant ones. Some conditions to achieve the better signal-to-noise ratio are considered when one uses the gated integrator. It is shown that: 1) at high counting rates the gated integrator is preferable for a peak detector, as far as noise is concerned; 2)at low counting rates the noise whitening filter-double integrator structure is prederable, it can be realized using monolithic technology. 9 refs.; 5 figs

[en] The dependence of the preamplifier equivalent noise charge (ENC) on the detector capacitance, shaping time and collector current of the head transistor is presented. The measurement results are in a good agreement with calculations based on a simple noise model, so tedious ENC measurements may be replaced by a simple selection of transistors on distributed base resistance and current gain factor and unsophisticated calculations. Soviet KT382 - type transistors have the same noise performance as the best Japan transistors NE578 and NE021 and it is possible to use it as a head transistor for nuclear electronics applications

[en] The low-noise preamplifier on bipolar transistors is described. Under zero detector capacitance it has the equivalent noise charge of 2100 el. (FWHM) and pulse response total length is 12 ns. The equivalent noise charge as a function of the detector capacitance and filter time constant are measured. 5 refs

[en] The structures of time-variant filters are considered. At low counting rates the noise whitening filter-double integration structure is preferable

[en] Nonlinear effects resulting in automodulation of fast magnetoelastic waves were observed in yttrium ferrite garnet films with epitaxial layer about 4 μm thick and substrate about 430 μm thick. The film was characterized by a high magnetostatic wave (MSW) attenuation. The MSW was excited in the H=1884 Oe magnetic field by metallic strips approximately 70 μm thick

[en] On the basis of temperature measurements of sound velocity (10-300 K) in niobium-phosphate glasses with rubidium it is shown, that their elastic relaxation results from competition of different mechanisms - through tunnel effect, thermoactivation relaxation, phonon anharmonism. Evaluation of relative participation of every competitive mechanism is carried out

No abstract available

[en] Main attention is given to investigating a low-frequency Raman light scattering and specific heat of Cd₂Nb₂O₇ in the assumed disproportionate phase between T₄=80 K and T₅=46 K. The anomalous behaviour of damping and intensity of the soft mode in this phase probably is explained by its interaction with the other low-frequency mode. The interaction of the modes permits to assume the existence between T₄ and T₅ quasistatic regions in which the long-range order and symmetry correspond to the low-temperature phase at T < T₅. The heat capacity behaviour studied versus different depths of sample cooling in the disproportionate phase also conforms to this assumption. The results obtained once more confirm the presence of T₃=83 K, T₄ and T₅ phase transitions, however, the problem on phase transition at T approximately 18 K is still open