Application of the Acoustic Emission Method for Estimating the Residual Life of Elastic Elements at the Stage of Preparing a Product for Operation

The article discusses the experimental substantiation of predicting the operational properties of elastic elements by the acoustic emission (AE) method, as well as the use of the non-destructive method of acoustic emission as an element of digital certification of critical mechanical and instrument engineering products.

Efficiency of using Artemia salina as part of a feed additive for chickens

Main problem: The development of the genetic potential of poultry, as well as the receipt of high-quality eggs for collection or further incubation, are possible only if rational and correct feeding of the broodstock and, more importantly, the young during its rearing period is observed. During this period, high-quality protein nutrition occupies an important place, which determines the level of productivity, stable growth, reproductive ability of the bird, as well as the state of health during the feeding period. Protein deficiency always remains an urgent problem for agricultural land, whose main activity is aimed at breeding dairy and meat animals. In this regard, research in the field of finding the use of non-traditional protein feed is of great need. If we summarize the modern achievements in the field of protein and aminoacid nutrition of poultry, we can find the most profitable way to obtain feed additives in industrial production. The studies, the results of which will be described in this article, are aimed at studying the possibility, experimental substantiation of the optimal dosage and the effectiveness of using the feed additive from crustaceans Artemia salina in the diets of chickens of the egg-meat direction of productivity [1]. Purpose: To study the possibility, experimental substantiation of the optimal dosage and the effectiveness of the use of the feed additive from crustaceans Artemia salina in the diet of chickens of the egg-meat direction of productivity. Methods: Analysis and generalization of theoretical information Results and their significance: This article presents the results of the analysis and generalization of theoretical material. The theoretical significance is determined by the fact that it is invested in scientific and practical problems related directly to solving urgent problems, increasing the efficiency, competitiveness and quality of domestic poultry products.

Experimental justification of sediment recirculation application

The article provides an experimental substantiation of the use of sludge as an opacifier and the use of its recirculation during sedimentation of suspended matter in horizontal sedimentation tanks. Based on the theory of agglomeration of suspended solids (Kalitsun V.N., and Laskov Yu.M.), the agglomeration coefficients can be calculated for treating water with one reagent and when using sludge recirculation for natural water purification.

Experimental substantiation of novocaine therapy for threatened abortion

Published in 1955 by R.A.Vortapetov and P.G.Zhuchenko data on the favorable result of treatment with novocaine in 80 women with threatening termination of pregnancy prompted us to experimentally study the nature of the effect of novocaine introduced into the vascular bed on the intensity of uterine contractions

Cavitation Effect in Ultrasonic-Assisted Electrolytic In-Process Dressing Grinding of Nanocomposite Ceramics

Ultrasonic-assisted electrolytic in-process dressing (UA-ELID) grinding is a promising technology that uses a metal-bonded diamond grinding wheel to achieve a mirror surface finish on hard and brittle materials. In this paper, the UA-ELID grinding was applied to nanocomposite ceramic for investigating the cavitation effect on the processing performance. Firstly, the ultrasonic cavitation theory was utilized to define the cavitation threshold, collapse of cavitation bubbles, and variation of their radii. Next, the online monitoring system was designed to observe the ultrasonic cavitation under different ultrasonic amplitude for the actual UA-ELID grinding test. A strong effect of ultrasonic cavitation on the grinding wheel surface and the formed oxide film was experimentally proved. Besides, under the action of ultrasonic vibration, the dressing effect of the grinding wheel was improved, and the sharpness of grain increased by 43.2%, and the grain distribution was dramatically changed with the increase of ultrasonic amplitude. Compared with the conventional ELID (C-ELID) grinding, the average protrusion height increased by 14.2%, while the average grain spacing dropped by 21.2%. The UA-ELID grinding reduced the workpiece surface roughness Rz and Ra by 54.2% and 46.5%, respectively, and increased the surface residual compressive stress by 44.5%. The surface morphology observation revealed a change in the material removal mechanism and improvement of the surface quality by ultrasonic cavitation effect. These findings are considered instrumental in theoretical and experimental substantiation of the optimal UA-ELID grinding parameters for the processing of nanocomposite ceramics.

Oxidative Aromatization of 4,7-Dihydro-6-nitroazolo[1,5-a]pyrimidines: Synthetic Possibilities and Limitations, Mechanism of Destruction, and the Theoretical and Experimental Substantiation

The reaction tolerance of the multicomponent process between 3-aminoazoles, 1-morpholino-2-nitroalkenes, and aldehydes was studied. The main patterns of this reaction have been established. Conditions for the oxidation of 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines were selected. Previous claims that the 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines could not be aromatised have now been refuted. Compounds with an electron-donor substituent at position seven undergo decomposition during oxidation. The phenomenon was explained based on experimental data, electro-chemical experiment, and quantum-chemical calculation. The mechanism of oxidative degradation has been proposed.

Biotechnology of families’ strength influence on the processes of sucrose inversion, dehydration and accumulation of monosaccharides

The purpose of the work is an experimental substantiation of biotechnological processes that ensure the maturation of honey during the processing of nectar by bees. During the whole period (7–9 days) of nectar treatment by bees there is a simultaneous partial dehydration of the liquid and biochemical transformations, among which the hydrolysis of sucrose and the accumulation of monosaccharides have the most significant effect on the quality of the mature product. In all series of experiments, the maturity of processed honey in the beehive at the water limit of less than 20 % occurs after 5–6 days of treatment by bees. The mature product in terms of water content remains open in almost completely filled cells for another 3–5 days, slightly reducing the water content from 19.78–20.07 % up to 16.40–18.38 %. Dynamic changes in the ratio of monosaccharides and sucrose in the process of nectar processing by bees, starting from the honey stomach during gathering from flowers to sealing in honeycomb cells have been detected. At the honey stomach-cell stage, a small amount of sucrose is hydrolyzed during the incomplete first day of processing and, as a rule, 0.48–4.11 % of monosaccharides calculated relative to the dry weight of the product are added. Sucrose inversion is more intense during the next 5–6 days, when a total of 12.94–31.42 % of splitted sugars are added, depending on their initial number and strength of families. The main processes of conversion of nectar into honey by bees are characterized by the advance of the reduction of water content in comparison with the splitting of sucrose and the accumulation of monosaccharides. According to the water content (less than 20 %), honey becomes suitable for pumping 3–5 days before it is sealed in the cells. The influence of the mass of bees of different families on the intensity of sucrose inversion in the cells and the accumulation of monosaccharides in the product has been experimentally proved. The maturity of honey in the ratio of sugars in the beehives of strong families is better than in weak ones.

EXPERIMENTAL SUBSTANTIATION OF MANURE FRACTIONATION ON PIG FARMS USING A SPIRAL-SCREW MECHANISM

The main vector of mechanization and automation of livestock farming at the present stage of technological development of producers is the improvement of resource-saving technologies and technical devices that enables agricultural producers to produce relatively expensive and high-quality equipment to improve conditions for the animals. This article was considered a method for effective fractionation of manure on pig farms to further obtain humus for soil fertilization. The optimal conditions for the performance of the presented gadget were identified, namely: the time spent by the manure mass in the rotor is 0.1, with a separation factor of 170 to 180, the partition for the filter is made of metal sheet with holes whose diameter varies from 0.8 to 1.5 mm and a thickness of no more than 1 mm. The device presented in the manuscript has several advantages in the form of automation, low energy consumption and cost, novelty, and high efficiency.

Electromagnetic radiation shielding composite coatings based on powdered alumina and ironoxide

The article presents the results of experimental substantiation of the method for improving the shielding properties of composite coatings based on powdered alumina (electrocorundum, alum earth), which consists in modifying the composition of such coatings by adding to it powdered iron oxide. This experimental substantiation consisted in the development of the technique for obtaining composite coatings based on powdered alumina and iron oxide, the manufacture of the experimental samplesusing the developed technique, measurements of electromagnetic radiation reflection and transmission coefficients values in the frequency range 0.7…17.0 GHz of the manufactured samples; implementation of the comparative analysis of the measured values with the similar values typical for the composite coatings filled with powdered alumina oxides, and composite coatings with the fillers such as powdered iron oxide. The obtained results revealed that by adding powdered iron oxide to the composite coatings based on powdered alumina oxides, it is possible to reduce by 1.0…8.0 dB their electromagnetic radiation transmission coefficient values in the frequency range 0.7…17.0 GHz. In addition, we found that the implementation of the proposed method allows one to decrease by 2.0…20.0 dB the electromagnetic radiation reflection coefficient values in the specified frequency range of the considered composite coatings, if such are applied to metal substrates. We propose to use the composite coatings, obtained on the base of the substantiated method, in order to ensure the electromagnetic compatibility of radio-electronic equipment.