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The article considers the problems and the possible consequences of the demographic crisis in Russia. It reveals internal and external sources of demographic problems of the country that make a threat to national interests. It substantiates the necessity to build demographic safety strategy in modern Russia. Providing demographic security involves security of national interests in the field of demographic development of the country as a principal condition of preserving the integrity of the Russian state and the growth of its reach spiritual and material potential.

This paper shows the nature of the variability of such adaptive properties of wheat as stability, resistance to stress, responsiveness and adaptability under the influence of electromagnetic treatment on the example of six varieties of spring wheat of Kazakh breeding. Among the studied varieties, only Akmola 2 variety, grown after pre-sowing seed treatment by electromagnetic field of ultrahigh frequency, differs simultaneously by complex of favorable signs - high stress tolerance and stability, relatively high genetic flexibility and low plasticity. Consequently, this plant variety is able to generate a high yield under different environmental conditions.

In the design of thermally stressed units in the sectors of mechanical engineering, aviation, aerospace, energetics it is often necessary to have information about the formation of the contact thermal resistance resulting from the discrete nature of parts metal surfaces contacting. While passing through the section zones of heat flows the temperature gradient increases, thus reducing the heat transfer capability of the contact junction and leads to thermal expansion of the constituent elements of the systems, relative shifts and warpages. The process of heat transfer through the zone of contact between metal surfaces having deviation of shapes in the form of nonflatness or waviness under conditions suitable to small mechanical loads is considered. The model of formation of the contact thermal resistance (CTR), in case of double contraction of the heat flow of channel and contact mаcrospots, caused by nonflatness or waviness, and then to microspots caused by roughness. Subject to the provisions of the theory of mechanical contacting of solids theoretical curves is derived describing the contact thermal resistance for compounds with surfaces having microdeviation or waviness operating in the regime of small mechanical loads. The results of physical experiments give satisfactory agreement with the calculated data. It was established that the presence of nonflatness or waviness on the contact surfaces increases CTR significantly as compared with rough surfaces. Increase of CTR is explained by the increase of wave height or equivalent nonflatness

In connection with the intensive development of new areas of technology, where heat-stressed systems are widely represented, there is urgent need of directed thermoregulation. To control the thermal conditions in composite systems it is required, in particular, to create connections with good insulation. The problem of increasing contact thermal resistance between the metal surfaces by introducing of mesh screens made of metal wire into the zone section is examined on condition the application of small loads not exceeding 1 MPa.