Search

Samples of La1-3xLixM2xCoO3-δ (M = Ca, Sr, Ba; 0≤x≤0,1) were synthesized by co-precipitation method. It is shown that the region of their homogeneity lies in the range of substitutions 0≤ x ≤0.05. The volume of the unit cell increases with the size of the alkaline earth metal that replaces lanthanum. Surface morphology of the obtained mixed oxides was studied by SEM. In all samples (except strontium - containing) paramagnetic Co2+ ions from the impurity Co3O4, which are in different local environments and have different degrees of exchange interaction with each other, are contained in the form of chain fragments -Co2+-O2--Co2+-O2--Co2+-O2— and contain defective centers Со2+, which are formed during the desorption of lattice oxygen from the surface, or in the process of diffusion of oxygen from the volume of material to the surface. In strontium-containing samples La0,85Lix0,05Sr0,01CoO3-δ there are mainly ferromagnetic clusters Co3+-Co4+.

Ukraine has been facing unprecedented challenges since 2014. A Revolution of dignity makes Ukraine turn closer to the EU and NATO, while ongoing and expanded Russian aggression threatens the very existence of Ukrainian statehood. One of the key directions of making Ukraine resilient to threats and challenges is the decentralisation process. It aims at making the government and public administration in Ukraine more democratic, transparent and efficient, open to public concerns and the needs and expectations of local communities. The article proposes analytical approaches towards the decentralisation process taking into account the imperative of democratisation and security challenges that Ukraine has been dealing with. The authors consider both dimensions of the national regional policy and self-government reforms, proposing a balanced vision on their advantages and disadvantages, as well as pointing out key problems that should be attended by the government. The process of decentralisation means a lot for Ukraine to make its statehood stronger and more secure vis-a-vis threats the country is facing now.