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Reasons for the appearance of “precursors” and “tails” in the analysis of pulsed operation mode of acoustic transducers by the method of integral transformations are considered. It is emphasized that the reason is the impossibility to make an accurate allowance for the actual dependence of the complex wave number on frequency over the entire frequency range.

Data on switching voltages and times of breakdown formation in nitrogen as functions of the gas pressure (in the range of 1–40 atm) and the degree of overvoltage of the discharge gap have been obtained in a subnanosecond interval at a uniform electric field. It is shown that the dependence of the breakdown formation time on the electric field and pressure obeys the similarity law, which indicates a multielectron character of discharge initiation.

All independent second- and third-order elastic coefficients were measured in the isotropic polycrystalline aluminum alloy AMg6 (Al–Mg–Mn system) using the Ritec RAM-5000 SNAP SYSTEM ultrasonic automated complex operating in the pulsed mode. The third-order elastic coefficients were determined using the Thurston–Bragger method from the experimentally measured velocity of shear and longitudinal elastic waves in AMg6 alloy as a function of uniaxial compression.

An electron gun with a cold cathode is developed for physical research with energy to 300 keV. The gun operates in the pulsed mode. Current amplitude is to 100 A, and pulse duration is 100 ns. The first results of the experimental investigation are represented.

Experimental results on the study of the output parameters of high-power continuous-wave (cw) laser diodes operating in the pulsed mode and the results of numerical simulation of the total efficiency of laser diodes with cavity lengths of 3 and 4 mm in a wide range of pump currents are presented. The spectral parameters of the high-power laser diodes are studied at various pulse-repetition rates. The possible causes of the limited output power in the pulsed mode are discussed.

The process of combustion of a hydrocarbon fuel in a pulsed mode is discussed on the basis of results of ramjet testing in an external flow modeling a Mach 5 flight.

It is experimentally shown that the pulse withstand capacity of transient voltage suppressors, independent of power rating, decreases by the same law with increasing pulse duration, which indicates their optimum design parameters. The interrelation between transition times (turned on and off) and the characteristic parameters of the transient voltage suppressor structure is shown. The possibility of emitting a power fraction at the resonance frequency is an additional stimulus to increasing the withstand power.

Morphology of tellurium deposits produced by pulsed electrolysis of 0.005–0.05 M TeCl4 solutions in dimethyl sulfoxide was studied. The effect of the TeCl4 concentration and pulsed current parameters on the structure of electrolytically deposited tellurium films was examined.

Results from analysis of the effect of changes in the ash layer structure on the layer’s physical parameters are presented. Principles of designing a system for pneumatic transportation of ash in a pulsed mode are selected.

A measuring complex for solving problems of fast neutron spectrometry using the time-of-flight method has been developed on the basis of an ЗГП-15 electrostatic tandem accelerator operating in a pulsed mode. The pulse repetition rate of the accelerator is 2.5 MHz, and the pulse duration is τ ≤ 1 ns. The accelerator components, some features of their performance, and their main parameters are described. The complex has been used to investigate the differential neutron emission cross sections for different constructional materials. A method providing the stable performance of its measuring channels has been proposed and tested.

Light-current, spectral, and temperature characteristics of long-wavelength (1.46–1.5 µm) lasers grown on GaAs substrates, with an active area based on InAs-InGaAs quantum dots, are studied. To reach the required lasing wavelength, quantum dots were grown on top of a metamorphic InGaAs buffer layer with an In content of about 20%. The maximum output power in pulsed mode was 7 W at room temperature. The differential efficiency of the laser, which had a 1.5-mm-long cavity, was 50%. The temperature dependence of the threshold current is described by a characteristic temperature of 61 K in the temperature range 10–73°C.

A new mechanism of pulsed laser oscillation based on ion-ion recombination is proposed. The advantages of utilizing this mechanism in a pulsed mode are considered, and the expected characteristics of the proposed lasers are estimated.

A simplified model of a cathode sheath sustained by electron avalanches is presented. The model is used to calculate the pulsed mode of a negative corona in nitrogen in order to establish the physical picture of the processes occurring in a pulsed corona. The most important point is that, in the pulsed mode, both the averaged and dynamic current-voltage characteristics of a glow cathode sheath are found to have a negative slope. Lowering the degree to which the glow cathode sheath is subnormal (by sharply reducing the sheath area) or switching on additional ionization mechanisms (e.g., stepwise ionization) that force the cathode sheath to evolve into a prearc spot causes the negative slopes of the averaged and dynamic current-voltage characteristics of the sheath to become more gradual and even positive, thereby stabilizing the discharge current.

The pulsed mode of a negative corona discharge in air has long been known; however, in electropositive gases, this mode has not been previously observed. This paper presents the results from a systematic study of a newly discovered pulsed mode of a negative corona in nitrogen over a wide range of experimental parameters. The conditions under which the pulsed mode is realized are described in detail. The dynamic characteristics of current pulses are determined. The shapes and parameters of current pulses in nitrogen and air are compared.

Previous publications concerned with the development and investigation of InAsSb/InAsSbP double heterostructure lasers emitting at 3–4 µm fabricated by liquid phase epitaxy are reviewed. In pulsed mode, the maximum operating temperature of the lasers is 203 K, the characteristic temperature is 35 K, and differential quantum efficiency is 20±5% at 77K. Mesa-stripe lasers with a 10-to 30-µm stripe width and a 200-to 500-µm cavity length can operate in CW mode up to 110 K. The total optical output power of more than 10 mW at λ=3.6 µm is obtained at T=82 K in CW mode. The output power per mode does not exceed 2 mW/facet. A single-mode lasing is achieved in the temperature range of 12–90 K.

We have produced, by using liquid-phase epitaxy, 2.7 to 3.0-µm lasers based on InAsSbP double-heterostructures with different phosphorus contents in the active and wide-gap regions. The lasers possess threshold current density ∼0.8 kA/cm2 at 77 K and operate in the pulsed mode up to ∼124 K with maximum threshold current density 10–12 kA/cm2. The lasers have a low series resistance ∼0.45 Ω.

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.

AlGaAsSb lasers with different Al concentrations in the active and confinement regions are fabricated and investigated. The structures lase in the region ∼1.6 μm. The AlGaAsSb solid solution in the active region is a direct-gap material with a small energy separation (∼56 meV) between the direct-gap Γ minimum and the indirect-gap L minimum of the conduction band. The lasers have a single-mode spectrum with a predominant longitudinal mode in the spatial distribution of the emission. The lasers operate at room temperature in a pulsed mode.

Avalanche light-emitting diodes based on porous silicon were studied with the aim of improving the efficiency of these diodes. The highest external quantum efficiency of 1.4% was attained in the pulsed mode of operation with an off-duty factor of 100, in which case the light-emitting diodes operated at the largest amplitudes of input currents. However, increasing the quantum efficiency with increasing input currents is limited by the attainment of the leveling-off region related to the thermal heating of the diode structure.