Vol 51 Iss. 3

The limits of the applicability of the concept of viscosity. In molecular physics, it is shown that the phenomena of diffusion, thermal conductivity, and internal friction in gases are based on a single mechanism - the transfer of mass, energy, and amount of motion from one gas layer to another by chaotically moving molecules. This commonality of the mechanism is manifested in the presence of a connection and mutual proportionality of the coefficients of diffusion, thermal conductivity and internal friction - viscosity...

The developed theory of mineral disclosure makes it possible to calculate all the main parameters of the processing process to obtain products of a given quality, if the technological methods fully realize the effect of a given crushing depth. In fact, the qualitative and quantitative indicators of existing coal enrichment processes differ significantly from the theoretical ones. This is explained by the insufficiently clear separation of particles with similar specific gravity and the impossibility of reliable enrichment of small classes of coal. Therefore, it is important to choose the right demarcation weight, at which the enrichment will be optimal. Most coals, in particular, of the Donetsk basin, are usually enriched in a specific gravity of 1.5, however, in some concentrates the ash and sulfur content remains high...

In recent years, a new field of knowledge has been developed — geoacoustics, which combines a set of acoustic methods designed to solve mining and geophysics problems. Depending on the specific tasks, the frequency range used covers the range from fractions of a hertz to megahertz. Modern geoacoustics is developing in several directions: sound location, acoustic logging, modeling of seismic processes, ultrasonic methods for studying the stress state of rocks...

In resonant measurements, the modulus of longitudinal elasticity E (Young's modulus) is determined for longitudinal vibrations, and the shear modulus G is determined for torsional measurements. For a rock sample in the form of a rod with free ends ...

In recent years, dichroic polaroids have been widely used to produce polarized light. Their advantages are their comparative cheapness, small thickness, large linear and angular aperture. The main disadvantages are the following. Transmission is selective across the spectrum, as a result of which the spectral distribution of energy in the studied light stream is significantly distorted...

The problem of studying physical phenomena during an explosion is currently very relevant. Some explosion processes have such short durations that only electronic equipment can detect them. The presence of a pronounced piezoelectric effect in some crystals, as well as in all ferroelectrics, makes it possible to develop low-inertia methods for measuring pressures, including shock wave pressure. Piezoelectric sensors have been used to study shock waves both here and abroad...

In the conditions of mining enterprises, the communication channel is usually the weakest link in the information transmission system. Particular violations of mining and geological and climatic conditions lead to its damage and, consequently, loss of information. Therefore, when measuring in hard-to-reach places and dangerous conditions, it is necessary to use communication channels that would be minimally affected by changes in external factors (for example, rails, pipes, grounding tires, trolleys or specially laid steel cables)...

The methods and technical means of mineral exploration are very diverse. One of them is the method of recording energy (brightness) contrasts of the earth's surface in the infrared region of the spectrum, which, in combination with others (photographic, magnetometric, etc.), can provide useful information. The article discusses the physical conditions of the existence of energy contrasts caused by the heterogeneity of the structure of the Earth's layers, as well as some questions about the possibility of registering and calculating them. ///

The most well-known focusing system for a beam of paramagnetic atoms is a six-pole magnet. However, the design and technology of its manufacture are relatively complex. In this article, a relatively simple magnetic focusing system is proposed...

Atomic and molecular beams are widely used in a number of quantum electronics and radio spectroscopy devices. The use of intensity modulators in these devices would simplify the task of beam indication, since amplification of weak variable signals is more technically simple than constant ones...

The causes of optical coloration of ferroelectric single crystals of barium titanate are different. For example, the color determined by impurities appears during their crystallization; dichroic — as a result of the absorption of polarized light passing through the crystal. The specific coloration of single crystals also occurs as a result of the interference of ordinary and extraordinary rays propagating in the crystal, as well as due to the dispersion and diffraction of light...

The issue of measuring the refractive indices of nickel carbonyl has been covered in only two papers. However, the purity of the samples used for measurements is not indicated in them; measurements were carried out for a small number of spectral lines and in a limited temperature range...

The cross section of the nickel carbonyl oxidation reaction was measured by studying the kinetics of the reaction. The amount of reacted substances was determined by the appearance of oxidation products in the reaction chamber using the optical method. As is known, the oxidation products of nickel carbonyl ...

When obtaining powdered nickel by the carbonyl method at an intermediate stage, it is necessary to monitor the degree of purification of nickel carbonyl from iron carbonyl. Currently, the content of iron carbonyl is determined by a chemical analysis lasting 6-8 hours. A faster method for monitoring the content of iron carbonyl in a product is proposed — optical, which can be used as the basis for an automatic analyzer...

Interest in studying the polarization of spectral lines by electron impact has increased significantly recently. This is especially true for measurements at the threshold of excitation ...

In recent years, various properties of low-temperature gas-discharge plasma have been increasingly used in gas-discharge devices, quantum amplifiers and generators, various light sources, plasma generators, etc. ...

Many phenomena in solids are associated with vibrations of their crystal lattice. The nature of Raman scattering of light and infrared absorption is almost entirely determined by the phonon spectrum of the crystal. Therefore, to study these phenomena, it is necessary to know the frequencies of lattice vibrations (phonons)...

In recent years, new photographic emulsions and other photosensitive materials for holography have been developed with resolutions ranging from hundreds to several thousand lines per millimeter. New methods and appropriate instruments were required for the resolvometric testing of such emulsions, since projection resolvometers are unsuitable for testing at spatial frequencies above 600-1000 lines per millimeter...

In recent years, new photographic emulsions and other photosensitive materials for holography have been developed with resolutions ranging from hundreds to several thousand lines per millimeter. New methods and appropriate instruments were required for the resolvometric testing of such emulsions, since projection resolvometers are unsuitable for testing at spatial frequencies above 600-1000 lines per millimeter...

The electrophysical properties of materials are influenced by many factors: humidity, temperature, granulometric and chemical compositions, etc. Therefore, the total differential, for example, of the volumetric resistance of saltpeter can be represented as ...

It is known that dissolved salts change the vapor pressure saturating the space above the liquid. There is no data in the literature on changes in mercury vapor density over amalgams. However, this phenomenon is of interest, since amalgams can occur on the electrodes of a number of gas-discharge devices, affecting the density of mercury vapor, on which the operation of the device depends...

As is known, alkali metal vapors ionize on the clean surface of a foreign metal if the output of the latter is greater than the ionization energy of the alkali atom. This phenomenon is explained by the occurrence of thermodynamic equilibrium in the metal-atom surface system during collisions...