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The kinetics of pulse conduction in silver chloride single crystals is investigated in the temperature range 12–300 K upon picosecond excitation with x-ray bremsstrahlung. It is found that the experimentally observed concentration of conduction electrons is nearly twice as high as the concentration of electron-hole pairs generated by an exciting pulse. This effect is associated with the chain multiplication of band charge carriers.

The temperature dependence of the pulse conductivity for CsI crystals upon excitation with an electron beam (0.2 MeV, 50 ps, 400 A/cm2) at a time resolution of 150 ps is investigated. Under experimental conditions, the time of bimolecular recombination of electrons and holes (V k centers) is directly measured in the temperature range 100–300 K. This made it possible to calculate the temperature dependence of the effective recombination cross section S(T)=7.9×10−8 T2 cm2. The temperature dependence of the conductivity σ(T) is interpreted within the model of the separation of genetically bound electron-hole pairs. The activation energy of this process is found to be E G =0.07 eV.

The first experimental results on the room-temperature pulsed conductivity of silver bromide excited in a pulsed mode by the X-ray bremsstrahlung radiation are reported. The data indicate that photosensitive materials are probably featuring the process of charge carrier multiplication during a time on the order of 10−9 s. The concentration of electrons in the conduction band of AgBr is estimated. The experimental concentration of the conduction electrons is about ten times greater than the concentration of electron-hole pairs created by the exciting radiation pulse.

The temperature dependence of the pulse conductivity σ for crystals of alkali halides with the NaCl-type lattice is measured at different densities j of excitation with an electron beam of picosecond duration. It is demonstrated that an increase in j leads to a weakening of the σ(T) dependence. This effect is due to the overlap of the wave functions of recombination centers and a decrease in the activation energy of separation of genetic electron-hole pairs.

A change in the electro-orientation spectrum followed by a change in the electric characteristics of bacterial cells had been measured when the barrier function of the cytoplasmic membrane was disordered under the action of damaging physical and chemical factors. Analysis of changes in the spectra at a frequency of 10(4) to 10(7) Hz allows one to estimate the degree of cell damage in quantitative terms. The paper presents the results of comparing three procedures for such an estimation: inoculation onto solid growth media; linear regression analysis of an electro-orientation spectrum; comparison of the electro-orientation effect at a high frequency (ca. 5 X 10(5) Hz) and at a medium frequency (ca. 10(4) Hz).

This paper discusses the temperature dependence of the pulsed conductivity of a KCl crystal in the interval 12–300K when it is excited by an electron beam (0.2 MeV, 50 ps, 300A/cm2) with a time resolution of 150 ps. It is shown that the electron lifetime is τ