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In the paper the effect of soil contamination by light and dark oil products on a rye (Secale cereale L.) and the prospects of using the plants with phytoremediation have been evaluated. Residual hydrocarbon oil concentration in the soil has been determined, phytoremediation may conduct not more than 5 g/kg of light and not more than 13 g/kg of dark oil

A comprehensive study of the quantitative and qualitative parameters of soil microfungi, bacteria and algae communities in the Apatity city, located in the subarctic zone of Russia, was carried out for the first time. Urban soil samples were taken from various landuse zones (residential, recreational) and compared to arable and forest soils. In the residential zone, a decrease in the number of microfungi in the topsoil horizon to 1.1 thous. CFU/g compared to 22.7 thous. CFU/g in forest soil was revealed. In the residential zone, an increase was found in the number of saprotrophic bacteria to 7.8 million cells g-1 and oligotrophic to 10.9 million cells g-1 compared to 2.6 million cells g-1 and 1.8 million cells g-1 respectively in forest soils. In the recreational zone, the number of soil micro-organisms was similar to that in the forest. A decrease in the species diversity of microfungi in the soil of the residential zone and an increase in the diversity of soil algae were revealed. Among the dominant species of fungi in urban soils, atypical species, including pathogenic ones for humans (Penicillium dierckxii, Stachybotris echinatus, Fusarium sp.), were found. In the algal community, diatoms, yellow-green algae, and cyanobacteria appeared in urban soils in comparison with forest soil. As a result of changes in the quantitative and qualitative indicators of soil microbial communities, a decrease in the enzymatic activity of soils has been noted. This may indicate a weakening of the ecosystem functions of urban soils and an increase in the degree of toxicity for living organisms and humans. [ABSTRACT FROM AUTHOR]

The analysis of algae and cyanobacteria in Albic Podzols affected by emissions of the copper--nickel plant Pechenganikel in the forest-tundra of the Arctic region was carried out. The main pollutants contained in the emissions and entering the soil are sulfur compounds and heavy non-ferrous metals. Algae and cyanobacteria were identified in soil samples collected in three zones differing in their distance from the pollution source: the zone of strong pollution (at a distance of 3 km southwest from the source of the emission), the zone of medium pollution (5-7 km), and the zone of weak pollution (16-25 km). In total, 61 species of eukaryotic algae and 2 species of cyanobacteria were found. In the studied soils, several species of algae were found with a high frequency, apparently resistant to unfavorable natural and anthropogenic factors: Chloromonas sp., Neocystis brevis, Parietochloris alveolaris, Pseudococcomyxa simplex, Stichococcus bacillaris, Interfilum terricola, Leptosira cf. obovata, Myrmecia bisecta, Nostoc musco- rum. Algae from the Chlorophyta division predominated in all soils studied. Yellow- green algae and diatoms were found only in the zone of strong pollution and were represented by a very small number of species. The presence of Microthamnion kuetzingianum, which is resistant to high acidity and heavy metals concentration, can be useful as an indicator of severe heavy metal contamination. Our study confirmed sensitivity of Vischeria magna to soil contamination with heavy metals. In long-term aspect, the species diversity of algae has increased by 35% in the soils influenced by the Pechenganikel plant in comparison with the data obtained 30 years ago, which probably indicates a certain decrease in anthropogenic load on the adjacent territories. [ABSTRACT FROM AUTHOR]

Aerogels are gels in which the liquid phase is completely replaced by a gaseous one. They form a new class of solids with a very low density, a large specific surface area and high porosity, which opens up wide possibilities for their practical application. ZrO2-SiO2 aerogels, due to the strong binding energy of Zr-O-Si, very low thermal conductivity, and the presence of acid and basic centers, exhibit excellent properties like aerospace heat insulators, selective sorbents, catalysts, and catalyst supports for high-temperature reactions. The traditional way of obtaining aerogels is formation of a branched, three-dimensional, irregular network of wet gels by sol-gel synthesis from alkoxides of elements, aging of gels, replacement of intermicillar water by organic liquids with low surface tension and careful removal of the solvent by drying under supercritical conditions or under ambient pressure. But alkoxides of the elements are expensive and toxic, drying at elevated pressures requires special equipment and is also expensive and energy-intensive, and drying at atmospheric pressure requires complicated and lengthy gel modifications. In this work, the task was posed, on the basis of the direct method of large-scale sol-gel synthesis of highly porous, nanostructured, spherically granulated zirconium silicates from aqueous solutions of cheap, accessible salts, to obtain materials of aerogel type, without resorting to lengthy equipmently and chemically complex methods of processing the resulting hydrogels. The gels were prepared by forming a zirconium carbonate complex from aqueous solutions of ZrOCl2 and K2CO3 and its subsequent interaction with a Na2SiO3 solution by their coagulation in a drop. The obtained strong spherical granules of ZrO2 SiO2∙nH2O hydrogel were thoroughly washed from impurities with distilled water and subjected to hydrothermal treatment for various times, followed by decantation with ethanol mixed with benzine or alkothermal treatment in this mixture in tightly closed containers at supercritical temperature for ethanol. The heat resistance of the samples was determined by calcining them in air at high temperature. Using SEM, XRD, and N2 adsorption / desorption methods, it has been found that the amorphous Zr-Si materials obtained containing 45 wt. % ZrO2 have a specific surface area of more than 500 m2/g, pore volume > 2 cm3/g, average pore diameter of ~ 18 nm, wide mesopores with a diameter of ~ 28 nm, bulk density less than 0.3 g/cm3, which typical for aerogels based on oxides of metal and silicon, and exhibit high thermal stability. [ABSTRACT FROM AUTHOR]

The analysis of algal-mycological complexes in Albic Podzolic soils affected by emissions of the Kandalaksha Aluminum Smelter (KAS) was carried out. The number and biomass of microscopic fungi in the maximum fluorine-polluted zone (fluorine-content >1000 mg/kg) more than 2 times lower than in distanced areas and amounted to 17.3 thousants colony-forming units/g and 1.33 mg/g respectively. Altogether, 31 species of soil fungi were isolated. The species Penicillium trzebinskii and P. miczynskii dominated the zone of maximum pollution. P. glabrum, P. spinulosum, and Memnoniella echinata prevailed in the zones of moderate pollution and background. The part of opportunistic fungi in contaminated soil increased in comparison with the background soil. The reduction of dark-colored fungi biomass in contaminated soil was noted. In total, 56 species of eukaryotic algae and 7 species of cyanobacteria were found. Among green algae, the species from families Chlorophyceae and Trebouxiophyceae dominated in all plots. In the zones of maximum and strong contamination, 53 algae species were found including xanthophytes, which were absent in unpolluted areas. The number of viable cells in the litter of the maximum contaminated soils varied from 100 thousand to 1.5 million in 1 g of absolutely dry soil. The species composition of algae and cyanobacteria in these soils showed the characteristic features of the Arctic biological soil crusts. [ABSTRACT FROM AUTHOR]

Dehydrogenation of propane to propylene in absence and in presence of oxygen in the reaction mixture of propane-inert gas has been investigated on vanadium oxide supported on mesoporous H-Ti-MCM-41 titanosilicate prepared by hydrothermal synthesis from titanoaerosil. It has been shown that at increase of the amount of VxOy from 5 to 30 wt. %, supported by decomposition of vanadyl oxalate or acetylacetonate complexes, the orderliness of system H-Ti-MCM-41 is broken, the size of its surface, diameter and volume of mesopores are decreased. The maximum yield of propylene is reached at 650-675 °C. It is obtained on 20 % greater for dehydrogenation of propane in the absence of oxygen. It is dependent extremally on the formed volume of pores, on its relationship with the acidity of active surface sites and it is accounted for the certain optimum range of variation of these values. [ABSTRACT FROM AUTHOR]

Ti-MCM-41 silicate with vanadium introduced in mesoporous structure has been obtained by hydrothermal template synthesis with participation of VOSO4 and pyrogenic titanoaerosil with 1.4 wt. % tetrahedrally coordinated titanium. By the X-ray diffraction, X-ray fluorescent spectroscopy, DR UV-vis analysis and adsorption of nitrogen it has been shown that even 0.3 wt. % V causes raising spatial order and hydrolytic stability of Ti-MCM-41. It has been found that additional supporting of VOx groups on a surface of the synthesized bimetallic silicate allowed to obtain the catalyst 5 %VOx/V, Ti-MCM-41 which due to dehydrogenation of propane generated propylene with bigger selectivity and yield than those when VOx was supported on MCM-41 and Ti-MCM-41. [ABSTRACT FROM AUTHOR]

In this work, new Bäcklund transformations (BTs) for generalized Liouville equations were obtained. Special cases of Liouville equations with exponential nonlinearity that have a multiplier that depends on the independent variables and first-order derivatives from the function were considered. Two- and three-dimensional cases were considered. The BTs construction is based on the method proposed by Clairin. The solutions of the considered equations have been found using the BTs, with a unified algorithm. In addition, the work develops the Clairin's method for the system of two third-order equations related to the integrable perturbation and complexification of the Korteweg-de Vries (KdV) equation. Among the constructed BTs an analog of the Miura transformations was found. The Miura transformations transfer the initial system to that of perturbed modified KdV (mKdV) equations. It could be shown on this way that, considering the system as a link between the real and imaginary parts of a complex function, it is possible to go to the complexified KdV (cKdV) and here the analog of the Miura transformations transforms it into the complexification of the mKdV. [ABSTRACT FROM AUTHOR]