The phytoremediation of industrial crops is becoming popular for the revitalization of land contaminated by trace elements (TEs). This approach combines biomass production with the improvement of soil health. To implement phytoremediation and derive sufficient dry biomass, crop production must be adequately supported by agricultural practices, including the application of bioinoculants. The current study aims to test the influence of several plant growth-promoting bacteria (PGPB), isolated from TEs-contaminated soil—i.e., Stenotrophomonas maltophilia KP-13, Bacillus altitudinis KP-14, and Pseudomonas fluorescens KP-16 and their consortia on the phytoremediation of the industrial crop M. × giganteus cultivated in the same TEs-contaminated soil. Contrary to expectations, the effects of PGPB on the biomass harvest were low. The most significant increase was detected in leaf biomass treated with a consortium of tested PGPBs. More significant effects were detected in the uptake of individual TEs. The phytoparameters of translocation factor, comprehensive bioconcentration index and uptake index were used to characterize the behavior of the TEs; Cr; Mn; Ni; Cu; Zn; Sr; V; and Pb in the presence of isolates. Plants treated with PGPB strains accumulated minimal concentrations of Cu and Pb in their aboveground biomass, while a tendency for Zn accumulation in the leaves and stems, and Sr accumulation in the leaves was observed. The obtained results reveal the combinations of isolates that lead to the minimal uptake of TEs into the stems and the simultaneous increase in DW. This study provides more insight into the leading factors of phytoremediation supported by PGPB and can be helpful when M. × giganteus is grown on TEs-contaminated soils of different origins.

Nowadays, the most common ways to dispose of acid tars and paper production waste are burial or incineration, but it is ecologically and economically expedient to use such waste in building materials. A new variant of filler aggregate—wastepaper sludge ash (paper production waste) and a chemical activator for filler aggregates—acid tar (oil-refining industry waste) is proposed. Elemental and mineralogical compositions of wastepaper sludge ash for comparison with commodity limestone mineral powder are established. Chemical activation of wastepaper sludge ash and limestone mineral powder was carried out and the wetting properties of the obtained materials were investigated by means of primary and neutralized acid tar. The physical and mechanical properties of stone mastic asphalt samples with different filler aggregate variants were studied. The possible chemical transformations in stone mastic asphalt using limestone mineral powder and wastepaper sludge ash activated by acid tar are shown. The possibility of replacing traditional limestone mineral powder with industrial wastepaper sludge ash has been proven, and the effectiveness of activating filler aggregates by acid tar has been confirmed. It was established that acid tar as an activator for filler aggregates does not require neutralization because stone mastic asphalt, in this case, demonstrates better properties compared to acid tar neutralization. As a result of our research, the application of wastepaper sludge ash is possible as a filler aggregate for stone mastic asphalt. And to obtain improved stone mastic asphalt characteristics, wastepaper sludge ash is required to activate 5 wt.% acid tar.

The impact of the plant growth regulators (PGRs) Stimpo, Regoplant, and Charkor on the production of the second-generation energy crop Miscanthus × giganteus on marginal post-military soil was investigated during two vegetation seasons. The land, previously a tank training polygon, has not been in use since 1990 and has become marginal. Biological parameters (stem, shoot, and root lengths) and dry biomass values were evaluated in relation to the applied treatments. The multivariate general linear model (M-GLM) results showed a positive influence of Charkor on M. × giganteus development; the effect was markedly higher in the second year of vegetation. The impact of Stimpo and Regoplant was less noticeable; nevertheless, certain combinations of treatments showed satisfactory results. The M-GLM approach detected the inter-influence of the main factors of the production process, i.e., PGRs, soil, and year of growing. The results showed the predominant influence of year, PGRs and combined factor PGRs × year on the biological parameters; the other studied factors and their combinations were not as effective. Further research should focus on verifying the field-scale results for the M. × giganteus plantation established in a post-military area and compare the lab and field studies.

The scheme of the integrated regeneration method for used mineral motor oils (UMMO) has been developed, according to which M-10DM and NORMAL 15W40 used oils were regenerated. A study on changes in physico-chemical properties, qualitative and elemental composition was carried out, and a mathematical model of the process was built. The further applications of the obtained products were proposed. Based on the obtained results, the technological scheme and flow chart of UMMO integrated regeneration were developed, and the process material balance was calculated.

Calcium dialuminate, CaAl₄O₇, nanopowders with a grossite-type structure, doped with chromium ions, were synthesized via the combined sol–gel solution combustion method. The evolution of phase composition, crystal structure, and microstructural parameters of the nanocrystalline materials depending on the temperature of the thermal treatment was investigated via X-ray powder diffraction and applying the Rietveld refinement technique. The photoluminescent properties of CaAl₄O₇ nanophosphors activated with Cr³⁺ ions were studied over the temperature range of 4.5–325 K. The samples show deep red and near-infrared luminescence due to the ²E → ⁴A₂ and ⁴T₂ → ⁴A₂ energy level transitions of Cr³⁺ ions under excitation in the two broad emission bands in the visible spectral region. The R lines emission reveals a strong temperature dependence. The feasibility of the material for non-contact luminescence sensing is investigated, and good sensitivity is obtained based on the (R2/R1) luminescence intensity ratio and the lifetime of the emission.

A series of strontium dialuminate SrAl₄O₇ nanopowders with the grossite-type structure doped with chromium and manganese ions were synthesized by the combined sol–gel solution combustion method with use of two different strontium salts. The Cr³⁺ and Mn⁴⁺ ions concentrations were varied from 0.05 to 5 at.%. Evolution of phase composition, crystal structure, and microstructural parameters of the nanocrystalline materials depending on the synthesis conditions, temperature of thermal treatment, and dopant content were investigated by the X-ray powder diffraction and the scanning electron microscopy techniques. Photoluminescent properties of SrAl₄O₇ nanophosphors activated with Cr³⁺ and Mn⁴⁺ ions were studied at room temperature. The samples exhibit typical photoluminescence in the deep-red spectral region, corresponding to d-d transitions in Cr³⁺ or Mn⁴⁺ ions. The intensity of this deep-red emission is dependent on the dopant concentration and annealing temperature. Features of the formation of octahedral surroundings around Cr³⁺ or Mn⁴⁺ ions are discussed.