34 results match your criteria: "Korkyt Ata Kyzylorda University[Affiliation]"

A new biopreparation is developed to clean soils from oil pollution in the arid climate of the Republic of Kazakhstan. The biopreparation includes bacterial strains F2-1, F2-2, and BS3701. When using the biopreparation in a liquid mineral medium with 15% crude oil, laboratory studies have revealed degradation of 48% n-alkanes and 39% of PAHs after 50 days.

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Water-Soluble Salts Based on Benzofuroxan Derivatives-Synthesis and Biological Activity.

Int J Mol Sci

November 2022

Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan 420088, Russia.

A series of novel water-soluble salts of benzofuroxans was achieved via aromatic nucleophilic substitution reaction of 4,6-dichloro-5-nitrobenzofuroxan with various amines. The salts obtained showed good effectiveness of the pre-sowing treatment of seeds of agricultural crops at concentrations of 20-40 mmol. In some cases, the seed treatment with salts leads not only to improved seed germination, but also to the suppression of microflora growth.

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The dimensional effect of electric charge storage with a density of up to 270 μF/g by the hydrated ZrO-nanoparticles system was determined. It was found that the place of localization of different charge carriers is the generalized heterophase boundary-nanoparticles surface. The supposed mechanism of the effect was investigated using the theory of dispersed systems, the band theory, and the theory of contact phenomena in semiconductors, which consists of the formation of localized electronic states in the nanoparticle material due to donor-acceptor interaction with the adsorption ionic atmosphere.

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This research focuses on the X-ray structure of 4,6-dichloro-5-nitrobenzofuroxan and of some of its amino derivatives ( and ) and on DFT calculations concerning the nucleophilic reactivity of . We have found that by changing the solvent used for crystallization, it is possible to obtain 4,6-dichloro-5-nitrobenzofuroxan () in different polymorphic structures. Moreover, the different torsional angles observed for the nitro group in and in its amino derivatives (, , and ) are strictly dependent on the steric hindrance of the substituent at C-4.

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Herein, we investigated the influence of two types of nanoparticle fillers, i.e., amorphous SiO and crystalline ZrO, on the structural properties of their nanocomposites with high-density polyethylene (HDPE).

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Herein, we report on the reaction of nitro-substituted azidobenzofuroxans with 1,3-dicarbonyl compounds in basic media. The known reactions of benzofuroxans and azidofuroxans with 1,3-dicarbonyl compounds in the presence of bases are the 1,3-dipolar cycloaddition and the Beirut reaction. In contrast with this, azidonitrobenzofuroxan reacts with 1,3-carbonyl compounds through Regitz diazo transfer, which is the first example of this type of reaction for furoxan derivatives.

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This study examines the adhesive properties and cytotoxicity of polyelectrolyte nanofilms from polyethyleneimine (PEI), polyallylamine hydrochloride (PAH) and sodium polystyrene sulfonate (PSS) on human bone marrow mesenchymal stromal cells (h-MSCs) and mouse adipose tissue (m-MSC) . Films are formed on 24- and 96-well culture plates in the combinations: PEI, PAH, PEI-PSS, PEI-PSS-PAH, PEI-PSS-PEI. An analysis of the culture results show that direct contact of h-MSCs with the PEI surface promotes adhesion (93-95% of adhesive cells versus 40% in the control).

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A series of novel 4-aminobenzofuroxan derivatives containing aromatic/aliphatic amines fragments was achieved via aromatic nucleophilic substitution reaction of 4,6-dichloro-5-nitrobenzofuroxan. The quantum chemistry calculations were performed to identify the factors affecting the regioselectivity of the reaction. The formation of 4-substituted isomer is favored both by its greater stability and the lower activation barrier.

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The reaction rates for the nucleophilic aromatic substitution of 4,6-dichloro-5-nitrobenzofuroxan with eight aliphatic amines (characterized by very different basicities/nucleophilicities) and three anilines have been measured in both methanol and toluene. The obtained rates have been related to the basicity (p in water and in benzene) or nucleophilicity ( Mayr constants) of the tested amines. The whole of the obtained kinetic data has furnished useful information on the high nucleophilic reactivity of benzofuroxan derivatives, which has been related essentially to two factors: the high electron-drawing ability/power of the condensed furoxan ring and the low aromatic character of the benzofuroxan system.

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