Using number theory, a formula is obtained that describes the thermal conductivities of ZrC, UC, UN, ThN, ZrN and ThxU1-xN at x = 0.2 and 0.5 with temperature change. This formula contains the atomic numbers of the elements, the thermal conductivities of the individual elements of the substance, and the structural parameter. There is no direct dependence on temperature in the formula, since it is hidden in the thermal conductivities of each element and in the structure parameter. In some temperature ranges, the structural parameter is constant; therefore, the thermal conductivity of some carbides and nitrides is expressed through summing the thermal conductivities of individual elements.

The thermal conductivity of the products of the interaction of molten core with concrete was derived using number theory. A formula has been found that describes the thermal conductivity of ZrO2, ZrSiO4, (U,Zr)SiO4 and UO2 over a wide temperature range. Formula is expressed in terms of the atomic numbers of elements, their valencies, the crystal structure of substances, and the thermal conductivities of individual chemical elements of the corium.

The article continues the search for a general law that describes the physical properties of a solid body, represented as a complex compound, through the physical properties of its elements. For a set of mixtures of metal oxides (actinide oxides), their melting or solidification temperatures were described in terms of the atomic weighted sum of the melting/solidification temperatures of these metals and molecular oxygen, multiplied by a variable which depending on the crystal structure and properties of melt of the compound and on the atomic numbers of the elements that make up the compound.

The article considers a way to compare large bulks of experimental data with theoretical calculations, in which the quality of theoretical models is clearly demonstrated graphically. Published theoretical data of the three-fluid dynamic model (3FD) applied to the experimental data from heavy-ion collisions at the energy range \sqrt{s_{NN}} = 2.7 - 63 GeV are used as example of application of the developed methodology. When analyzing the results, the quantum nature of the fireball, created at heavy ion collisions, was taken into account.

Various threats of terrorist attacks on the social infrastructure arise due to strengthening of terrorist organizations, both in the context of their coming to power in certain countries (Afghanistan), and their association with the drug business, which significantly increases the financing of terrorist structures, allowing them to acquire modern weapons. Unmanned aerial vehicles (UAVs) are cheap, readily available and capable of carrying containers of lethal agents, what make them a common means of terrorist attack. Effective protection of critical industrial facilities from UAV terrorist attacks is an important task for improving systems and means of electronic warfare against terrorism. This paper considers the possibility of detecting an UAV near a critically important industrial facility using small-sized radar stations (SRS) placed on board of UAV-interceptors. Typically, SRS are placed on board drones for radio mapping of the terrain, operational-tactical and reconnaissance combat missions, and rescue operations. The possibility of using SRS on board interceptor drones to detect intruder drones as an additional channel to a remote radar channel has not been considered anywhere before. The paper provides a review of existing small-sized radar stations (SRS) that can be used or are used on-board of UAVs, as well as a review of existing UAV-interceptors. It is shown that UAV-interceptors equipped with SRS can be used to fly around the area about a critical industrial facility, by analogy with overflights performed by multicopters around agricultural areas, with recharging in specially equipped places for this at different distances from the control center and from critical industrial facility. A method is proposed to increase the existing optical and acoustic channel for detecting an intruder drone by an order of magnitude, and the radar channel by 5 km, if not only small-sized radar, but also optoelectronic with the acoustic UAV detection system are installed on the UAV-interceptor with the integrated use of these channels with remote radar UAV detection system.