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Purpose. Investigate the effect of additive formation parameters on the properties of an antistatic composition based on polylactide (PLA). Methodology. Surface and bulk electrical resistance were determined by ASTM D257 Findings. The influence of additive formation parameters on the electrical properties of graphite-filled composite based on polylactide has been studied. It was found that the value of resistivity significantly depends on the printing conditions, namely the temperature, speed, thickness of the layer. Increasing the printing temperature helps to reduce the resistivity of the sample. Reducing the thickness of the polymer layer also reduces the resistivity at a print speed within 3000 mm / min It was found that the specific electrical characteristics are significantly different in the plane of the sample in contact with the printing platform. Concentric method of laying layers of polymer melt is less effective in terms of resistivity than mutually perpendicular. It was found that the electrical resistivity of samples made of material for 3D printing, which was previously subjected to drying below the resistance of the sample made of undried material. The programmed change of 3D printing parameters allows to control the specific resistance of graphite-filled composite based on polylactide in the range of three orders and to obtain products with properties from antistatic to statically dissipative materials. Additive production allows to obtain products of the desired configuration with adjustable electrical properties. Originality. The peculiarities of the change of antistatic properties of the polymer composite depending on the conditions of additive formation of experimental samples are investigated. Depending on the applied parameters of additive molding, it is possible to obtain products with properties from antistatic to statically dissipative materials. Practical value. Technological modes of additive molding of composite products based on polylactide and graphite have been developed. Energy consumption for additive formation of products of different mass is estimated. [ABSTRACT FROM AUTHOR]

Nutrition of military personnel in the field or during combat operations is of great importance for maintaining force performance. An indispensable element in the provision of service personnel with food is individual "dry rations", which are most often formed based on the nutrition of one soldier for one to three days. Of interest was the question of how the nutrition of the service personnel changed in combat operations meanwhile. Objective - to study the historical aspect of nutrition in battle conditions during the period from the Zaporizhzhia Sich to the present day. Materials and methods - literary sources, regulatory documents, research results. The information retrieval and the theoretical analysis method are used. The literature data, legislative and regulatory documents, the results of scientific research related to the nutrition of Ukrainian service personnel in the combat operations for the period from XVII-XXI centuries are analyzed. The evolution of "dry operational ration" over several centuries took place depending on the development of the food industry: from dry products that do not spoil with long-term keepeng (crackers, cereals, dry meat, dry fish), dry food concentrates and canned foods to readyto- eat first and second courses. The caloric content of dry rations from the middle of the twentieth century ranged from 3100 kcal to 3350 kcal. In the Ukrainian army it is from 3,500 kcal to 3,800 kcal, and only for Joint Force Operation (JFO) - 4,100. Until recently, the energy value (calorific value) of dry rations was calculated without taking into account the actual energy consumption of service personnel in carrying out combat operations. Further studies on improving the nutritional standards of service personnel should be aimed, first of all, at establishing real energy costs when they perform their mission, including military ones. [ABSTRACT FROM AUTHOR]

The article describes the effectiveness of the mixing apparatus of feed additives for animals with a horizontal and vertical mixing device. The characteristics of the interaction of a particle with a mixer blade are considered. The analysis of the trajectory of the particle during its contact with the blade. The processes of obtaining a multicomponent liquid mixture in devices with horizontal and vertical blade shaft are considered. The main characteristics of the process are presented in the form of similarity criteria. Empirical equations for the dependence of the parameters of the mixing process on the factors are obtained. The results of the study are presented in the form of graphs. The optimal parameters of the apparatus with a mechanical mixing device are indicated, providing a resource-saving mode of operation while maintaining the efficiency of the mixing process. The factors of the mixing process that affect the amount of energy consumption are determined. [ABSTRACT FROM AUTHOR]