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This relatively low-temperature process involves complete rearrangement of the crystal structure-from a 2D architecture featuring slabs [Pb 2 F 2 ] 2+ formed by fluorine-centered tetrahedra into a structure characterized by 1D motifs based on [OPb 2 ] 2+ chains of oxocentered tetrahedra. The comparative crystal chemistry of the obtained anion-centered structural architectures is discussed. (Siidra et al. 2013c(Siidra et al. , 2015. Most of these structures can be notionally decomposed into tetragonal subcells with an a parameter similar to that of litharge (commonly 3.75-4.35 Å, depending on the layer composition), while c can vary over a wide range (from 5 to more than 75 Å) as might be expected for layered structures (Charkin 2008). Within these "archetypic" subcells, the 2 ∞ [XM] (X = anion, M = cation) slabs contain two X and two M atoms; they are positively charged and interleave with various anionic species. The OM 4 oxocentered tetrahedra, with M = Pb 2+ , Bi 3+ or rare-earth elements, are the most common contributors to these slabs. Second rank the FM 4 fluoride-centered tetrahedra with M being rare-earth or alkaline-earth elements, but most commonly Pb 2+ . [Pb 2 F 2 ] 2+ slabs have been found in the structures of the minerals matlockite [Pb 2 F 2 ](Cl) 2 (c = 9 Å) (Pasero and Perchiazzi 1996), grandreefite [Pb 2 F 2 ](SO 4 ) (c = 14 Å)

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The technological inspection of the electrolyte composition in aluminum production is performed using calibration X-ray quantitative phase analysis (QPA). For this purpose, the use of QPA by the Rietveld method, which does not require the creation of multiphase reference samples and is able to take into account the actual structure of the phases in the samples, could be promising. However, its limitations are in its low automation and in the problem of setting the correct initial values of profile and structural parameters. A possible solution to this problem is the application of the genetic algorithm we proposed earlier for finding suitable initial parameter values individually for each sample. However, the genetic algorithm also needs tuning. A self-configuring genetic algorithm that does not require tuning and provides a fully automatic analysis of the electrolyte composition by the Rietveld method was proposed, and successful testing results were presented.

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The paper deals with the production and study of nanocomposite powder paints based on alumina nanofibers. For nanodispersed fillers, the nature of the surface states on the filler particles is important. The problem of introducing nanomaterials into a polymer matrix cannot provide an effective solution without matching the surface states of the nanomaterial filler and the polymer matrix for the resulting composite materials. The consistency of the surface states of the nanomaterial filler and the polymer matrix determines the quality of transfer of the necessary properties to the resulting polymer composite. In order to increase the affinity of alumina nanofibers with a matrix of powder paint, the nanofibers were treated with 3-glycidyloxypropyltrimethoxysilane (GLYMO) in toluene. It is shown in the work that the addition of alumina nanofibers leads to a hardening of the coating, an increase in its elasticity, and an increase in corrosion resistance. Finishing of alumina nanofibers in a solution of silane in toluene leads to its functionalization, which is sufficient for the distribution of nanofibers in the polymer matrix of the paint and improvement of its operational properties.

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