Химия

The onе-pot interaction of C-aminotetrazole, cyclohexanone and o-R-benzaldehydes (in contrast to unsubstituted benzaldehyde benzaldehyde) leads to the formation of additionally linear tetrazohexahydroquinazolines, their isomers with an angular articulation of the rings. The appearance of isomers with angular articulation of the rings can be explained by the total influence of the spatial and electronic effects, and the influence of the low-energy interaction by the type of hydrogen binding NH ··R (VVS) can not be ruled out.

Cefazolin is a cephalosporin antibiotic of the third generation. It is widely used in medical practice for the therapy of various infectious-somatic pathologies. The work was aimed at the creation of solid-contact potentiometric cefazolin-selective sensors. For the first time, polyaniline was used to stabilize the potentials of solid-contact sensors. As the membranes active components, the compound of tetradecylammonium (TDA) with the silver (I) – cefazolin complex were applied.

Presently, the bentonite clays are the popular materials which used in the adsorption refining. The bentonite is characterized by the extensive surface, the high mechanical strength, also it is the cheap and affordable material. In comparison with another cheap natural sorbents, the bentonites are differenced by the high sorption capacity towards to the anions of the various salts. However, the natural bentonite undergoes modification for more effective purification.

Composite films were obtained from a mixture of starch, polyvinyl alcohol, and a plasticizing additive based on aspartic acid. The surface morphology, structural features of the composites, and their behavior in a polythermic mode were studied by scanning electron microscopy, X-ray diffractometry, IR spectroscopy, differential thermal and thermogravimetric analysis. Only carbon dioxide was detected in the gaseous products of thermal decomposition of the samples. The sorption and physico-mechanical properties of our composite films were analyzed.

The scientific literature in English for 2000–2017, devoted to the problem of the development of sorbents based on polymeric materials, intended for collecting spilled oil and oil products from the surface of reservoirs, has been scanned and analyzed. Three most numerous classes of polymeric sorbent materials (cellulosic materials, acrylate copolymers and synthetic rubbers) have been identified, and the oil sorbents proposed are characterized. Prospects of using sorbents of these classes for cleaning up the surface of reservoirs from oil spills are discussed.

Superparamagnetic magnetite nanoparticles (MNP) have gained much attraction from the beginning of 21century because of its potential applications in biology, medicine, theranostics, physics, chemistry and chemical analysis due to unique multifunctional properties, including small size, superparamagnetic behavior, low toxicity, high adsorption properties used for magnetic solid-phase extraction (MSPE) in water purification and chemical analysis.

Lanthanide complexes with organic ligands (including hydrocarbons) find application in medicien as luminescent biomarkers for various pathogenic bacteria. At the same time, starch (as a polysaccharide) can serve as a source for carbon nanoparticles (via thermal decomposition) that have very intensive and longliving luminescence, thus such nanoparticles conjunctioned with lanthanides may be used to create more effective medical probes.

The process of catalytic reforming remains one of the main processes of the modern petrochemical industry, allowing for obtain commodity products – gasoline, with high detonation resistance and raw materials for the petrochemical industry – aromatic hydrocarbons. One of the most important tasks of improving the reforming process is the development of new efficient catalytic systems that don’t have noble metals in their composition.

Oil spills after tanker and pipeline accidents pose a serious threat to the environment, lead to the loss of energy carriers and severely pollute seawater. Mechanical extraction by sorption mechanism is an effective means of oil spill liquidation from the surface of reservoirs.

Silicon-containing glycerohydrogel thin-film plates based on chitosan L- and D-ascorbates were obtained by means of biomimetic sol-gel synthesis using silicon tetraglycerolate as a biocompatible precursor. Their stress–strain characteristics were studied. For all the samples of our glycerohydrogel plates, stress–strain curves were recorded, characteristic of soft plastic polymeric materials not reaching their yield point under tensile conditions. At rupture, the material shows some characteristic signs of macroscopic plasticity.