Aggregation of an Autonomous System with an Attracting Cycle

Automation and Remote Control - We consider a set of autonomous systems in each of which a case that is nondegenerate for a periodic solution is realized. The problem of aggregating these systems...     

Comparative Analysis of the Electroluminescence Efficiency in Type-I and Type-II Heterostructures Based on III–V Narrow-Gap Compounds

Semiconductors - We study in detail the mechanisms of radiative and Auger recombination in type-I and type-II heterostructures based on III–V narrow-gap materials. The presence of a...     

Mechanical activation-assisted electro-thermal explosion synthesis of the Ti2AlC phase

This study deals with the synthesis of the Ti₂AlC phase using the Electro-Thermal Explosion under Pressure with Confinement (ETEPC) technique. The effects of the ETEPC technique and the milling process parameters on the TiC_x phase content and the formation mechanism of the Ti₂AlC phase were investigated. The latter is mainly affected by the morphology of the powder mixture and aluminum melted amount. The optimization of the above parameters allowed the achievement of the desired reaction, leading to the formation of the Ti₂AlC phase with a purity of about 97?wt%. The results clearly demonstrate that the ETEPC process enables one to control both time and material synthesis temperature.     

The process of electrochemical deposition of zinc in the presence of boron-doped detonation nanodiamonds

The influence of detonation of nanodiamonds doped with boron during the detonation synthesis (DND-boron) on the process of electrochemical deposition of zinc from a zincate electrolytic solution is investigated. It is shown that the throwing power (the coating uniformity) increases 2to 4-fold depending on the DND–boron concentration, the electrolytic conductivity remains unchanged, the corrosion resistance (as measured by the corrosion currents) of the Zn–DND-boron coating grows 2.6 times when tested in the 3% NaCl solution and 3 times in the climatic chamber.     

The Influence of the Shape of Model Hydrometeors on the Formation of Discharge between an Artificial-Thunderstorm Cell and the Ground

We have experimentally studied how arrays of model coarse hydrometeors influence the initiation and propagation of discharge between an artificial-thunderstorm cell of negative or positive polarity and the ground. It is established for the first time that the probability of initiation and stimulation of a channeled discharge between negatively or positively charged cloud and the ground significantly depends on the shape and size of coarse hydrometeors occurring near the thunderstorm cell boundaries. The obtained results can be used in developing methods for the artificial initiation of the cloud–ground type lightning of both polarities and targeted discharge of thunderstorm clouds.     

A new carbon structure in annealed film coatings of the carbon–lead system

Carbon–lead solid solutions coexisting with amorphous carbon have been obtained for the first time in a film coating deposited by ion-plasma sputtering. During subsequent vacuum annealing of carbon–lead films containing more than 68.5 at % Pb, this element almost completely evaporates to leave an amorphous carbon coating on a substrate. During annealing at 1100°C, this amorphous carbon crystallizes into a new hexagonal lattice with unit cell parameters a = 0.7603 nm and c = 0.8168 nm. Characteristic X-ray diffraction data for the identification of this phase are determined.

     

Influence of temperature on the speciation of radionuclides sorbed onto rocks from the Nizhnekansky massif

The influence of temperature on speciation of actinides (Pu, Am) and some fission products (Cs, Sr), sorbed from simulated groundwater onto rocks from the Nizhnekansky massif (gneiss, dolerite) under anaerobic conditions at 20 and 90°С, was studied by sequential extraction. An increase in the contact temperature leads to an increase in the radionuclide uptake percentage and, in some cases, in the content of tightly fixed forms. The radionuclide species undergo redistribution with time.     

An image-brightness amplifier based on copper bromide vapor for operation at increased superradiance pulse duration

We present data on the development and application of an image-brightness amplifier based on copper bromide vapor intended for the visualization of objects occurring at distances above 5 m from the detecting equipment. An increase in the superradiance (gain) pulse duration was achieved by decreasing the repetition frequency of pumping pulses (to 3 kHz) and increasing the capacitance of the capacitor bank (up to 3.4 nF) so as to increase the deposited pulse energy. The basic possibility of creating active optical systems with brightness amplifiers (laser monitors) for the visualization of objects and processes occurring at large distances from a registration system is demonstrated.     

A mass spectrometer for pain-response monitoring in rats

A mass spectrometer with a membrane interface has been used for measuring the relative concentration of carbon dioxide (CO₂) released from rat skin in response to thermal irritation and pain stimulus during intraperitoneal propofol–lidocaine anesthesia. It is established that the local anesthetic lidocaine directly influences the central nervous system and induces antinociceptive reaction to thermal irritation.