Development of the optical electronic setup for carrying out measurements by multicolor Particle Image Velocimetry

The paper is devoted to development of the optical electronic setup for carrying out measurements by multicolor particle image velocimetry. The main advantage of this method is the ability to visualize vector velocity fields in several planes simultaneously. As a result a 3D model of a setup was developed, a laboratory sample was assembled and series of testing experiments were performed. As a test object, vortex structure formed by a chemical stirrer in a cuvette with liquid has been considered. The experimental data were compared with the computer model developed in SolidWorks and FlowVision software.

DEVELOPMENT OF A BIODEGRADABLE MATERIAL FOR BONE REGENERATION BASED ON SILICON COMPOUNDS

In the course of this study we established that the laboratory sample in granulated form developed by us has a stimulating effect on the growth and proliferation of osteoblasts. Analysis of the data (CT, MRI) of the biological material obtained from the animals withdrawn from the experiment showed a statistically significant replacement of the artificial defect with bone tissue with signs of restoration of the cortical plate. The analysis of the CT results indicates that this method is sufficiently informative in assessing the regeneration of the trabecular structure of bone tissue. The study (MRI) of the bone material obtained from the animals participating in the experiment showed that when the osteoinductive material was integrated, the defect zone was replaced by 90%. In the projection of the defect, the newly formed tissue of a homogeneous structure was determined, corresponding in density to bone tissue with a high degree of mineralization. There was a complete restoration of bone tissue in the projection of the defect.

Automated Fiber-Optic System for Monitoring the Stability of the Pit Quarry Mass and Dumps

This article ls with the issues related to the development of a system for monitoring the deformation and displacement of the rock mass leading to the collapse of the quarry sides. Monitoring system uses point-to-point fiber-optic sensors. Fiber-optic sensors and control cables of the communication line are made based on the single mode optical fibers, which allows to measure with high accuracy the deformations and displacements of the rock mass at a distance of 30-50 km. To create fiber-optic pressure sensors, an optical fiber of the ITU-T G. 652.D standard is used. Laboratory sample is developed concerning the point fiber-optic sensor made based on the two-arm Mach-Zender interferometer using a single mode optical fiber for monitoring strain (displacements) with a change in the sensitivity and a reduced influence of temperature interference leading to zero drift. The article presents a mathematical apparatus for calculating the intensity of radiation of a light wave passing through an optical fiber with and without mechanical stress. A laboratory sample of single mode optical fibers based on the Mach-Zender interferometer showed a fairly high linearity and accuracy in the measurement and can be used to control the strain of the mass after appropriate refinement of its design. Mathematical expressions are also given for determining the intensity of the light wave when the distance between the fixing points of a single mode optical fiber changes depending on the change in the external temperature. A diagram for measuring strain using a point fiber-optic strain sensor is developed. Hardware and software package is developed, which can be used to perform a number of settings of measuring channels. The work is aimed at solving the production problems of the Kenzhem quarry of AK Altynalmas JSC.

IMPROVING DEGRADED AGRICULTURAL MOUNTAIN LANDSCAPES BY THE SLITTING METHOD

The article examines a laboratory sample of a maneuverable unit for slitting mountain meadows and pastures. Its design is adapted for work in a mountainous agricultural landscape with degraded soils having a slope of cultivated areas up to 15°. The study object is the structural, technological, operational, and agrotechnical parameters of the laboratory sample and the graphic-analytical rationalization of the working process of slitting on the slope. The technical tests of the laboratory model were carried out in Dargavs, RNO-Alania, at an altitude of 1540 meters above sea level with a slope steepness of up to 15°. The authors determined the indicators of test conditions and functional operation in accordance with GOST 33687-2016. The laboratory sample of a slitter (paraplow) mounted on the “Fenshaw-180” mini-tractor was adapted to a mountain zone with a reverse (obtuse) angle of penetration into the soil. The authors off er an optimal scheme for the arrangement of the working tools of the slitter. They determined the technology of its traveling along the slope and the design of the working tools providing the distance between the slits of 1000 ± 5 mm, the slitting depth of 200…220 mm, the slit width of 10…30 mm ± 5 mm. The considered sample of the unit for slitting mountain meadows and pastures will improve the moisture and air supply of the lower soil layers; reduce the degradation processes of slope areas, increase labor productivity, environmental sustainability, and grassland farming effi ciency.

Infrared Radiofluorescence (IR-RF) of K-Feldspar: An Interlaboratory Comparison

Infrared Radiofluorescence (IR-RF) is a relatively new method for dosimetric dating of the depositional timing of sediments. This contribution presents an interlaboratory comparison of IR-RF measurements of sedimentary feldspar from eight laboratories. A comparison of the variability of instrumental background, bleaching, saturation, and initial rise behaviour of the IR-RF signal was carried out. Two endmember samples, a naturally bleached modern dune sand sample with a zero dose and a naturally saturated sample from a Triassic sandstone (~250 Ma), were used for this interlaboratory comparison. The major findings of this study are that (1) the observed IR-RF signal keeps decreasing beyond 4000 Gy, (2) the saturated sample gives an apparent palaeodose of 1265 ± 329 Gy and (3) in most cases, the natural IR-RF signal of the modern analogue sample (resulting from natural bleaching) is higher than the signal from laboratory-induced bleaching of 6 h, using a solar simulator (SLS). In other words, the laboratory sample bleaching was unable to achieve the level of natural bleaching. The results of the investigations are discussed in detail, along with possible explanations.

External calibration methods for radar polarimeters

Methods of external calibration of radar polarimeters are considered. Algorithms for evaluating elements of the Mueller matrix and eliminating distortions introduced by the polarimeter are presented. The article describes the design of a radar reflector with electrically controlled polarization properties that can imitate the properties of two and three-sided reflectors and non-reciprocal reflectors. The analysis of the mode of dynamic switching of the scattering characteristics of the reflector used for calibration by the method of polarization modulation of scattered signals is performed. The results of experimental studies of a laboratory sample of a radar reflector with controlled characteristics are presented. The results obtained can be used in radar.

Testing of laboratory samples of microbiological preparations based on promising producer strains for the control of apple scab

To prevent phytosanitary destabilization in apple agrocenoses, it is necessary to include ecologically safe microbiological preparations in the protection systems. In the Krasnodar region in 2016 and 2019 in the field, laboratory samples of microbiological preparations were tested in the formulation “wettable powder” from the collection of the laboratory of the biological method of the FGBNU VNIIMK against Venturia inaequalis (Cooke) G. Winter. Of the 9 laboratory samples tested in 2016, the highest efficiency, approaching the effectiveness of a chemical fungicide, was shown by samples based on fungal producer strains: RK-1, XK-1 and T-2 - 76.9-92.5%. In 2019, all variants (in the amount of 4) using laboratory samples of microbiological preparations were more effective in comparison with the active substance of chemical origin. The best scab control was provided by a laboratory sample of a three-component mixed preparation based on two fungal and one bacterial producer strain RK-1 + XK-1 + B-12 - 83.0-84.9%. The isolated samples are promising for research on the creation of microbiological preparations against apple scab.

Using the roller threshing device for threshing fiber flax

The ways of increasing efficiency of the factory technology for harvesting fiber flax with threshing stem band from the rolls were studied. The experiment was carried out in stationary conditions with a moisture content of the source material of no more than 16%. A roller threshing device was proposed for separating the seed part of the crop from the stem before feeding stems into the fiber production line. The device ensures threshing of the fiber flax stem band over its entire width without using a separate clamping conveyor. The places where the seed heap descends from the roller threshing device while threshing flax stem band were identified. Quality indicators of the roller threshing device operation were obtained ensuring 100% threshing of the fiber flax band with a band compression force between the rollers of 16 kN. With this method of threshing, damage and crushing of seeds were not noted, the stems were evenly flattened along their entire length. Fractional composition of the threshed heap was determined during threshing of a fiber flax stem band between the rolls of the laboratory sample of a three-roll threshing device: loose seeds (50%), shells of capsules with fruitstalks (47), capsules with seeds (3), heap of leaves and stems (less than 1%). The results of the study in stationary conditions showed the expediency of using roller working bodies to separate the seed part of the crop from the stem part for the technical support of the factory technology for harvesting fiber flax. The use of roller working bodies in the design of threshing devices without a separate clamping conveyor allows to increase the quality and quantity of flax products obtained both in seeds and in fiber due to the improvement of the process of gentle flattening of the stem band between the rollers along its entire width. The concept of this roller threshing device is advisable to use when designing trailers and travelling flax harvesting machines for the implementation of a separate technology for harvesting fiber flax.

Mechanisms of charge accumulation in electrochemical systems formed based on of nanoporous carbon and manganese oxide

In this work, the processes occurring in electrochemical systems based on nanoporous carbon material and manganese oxide in an aqueous solution of lithium sulfate are analyzed. Furthermore, it is shows the feasibility of these materials combination cycling as electrodes of a hybrid electrochemical capacitor. The combination of electrode materials with different mechanisms of charge accumulation was determined. Consequently, an increase in the accumulated energy by more than 25% by the formation of an electric double layer and the occurrence of redox reactions based on carbon and manganese oxide respectively. The laboratory sample of an aqueous electrolyte hybrid electrochemical capacitor was formed. Moreover, the laboratory sample is electrochemically stable at an operating voltage of 2 V.