Химия

The sorption properties of some sands selected in the coastal zones of economically important, but at the same time ecologically oppressed territories of Vietnam are considered. The purpose of the research is to assess the absorption capacity of sands in relation to emulsifi ed petroleum products, to identify their ecological role in typical situations of spillage of small amounts of toxic substances. It is shown that the sorption qualities of the sands depend on the location of the sands, their geochemical and granulometric heterogeneity.

Unlike antibiotics and heavy metals, nucleic acids exist in the aquatic environment as a part of prokaryotic and eukaryotic microorganisms (bacteria, fungi, etc.) rather than in a free form. In this regard, the most important primary stage of sample preparation of an object for the quantitative analysis of DNA and RNA in natural and wastewaters includes membrane ultrafi ltration of an aqueous sample, followed by its sorption preconcentration on a solid phase carrier.

Molecular imprinting is a rapidly developing and promising approach for the selective recognition for target molecules of diff erent nature. In this review, we have collected works devoted to synthesis and application of polyaniline-based molecularly imprinted polymers (MIPANI) over the last 5 years. The manuscript provides brief descriptions of the main approaches to the synthesis of PANI MIPs and the advantages and disadvantages of each technique.

The transport processes occurring in polymer matrix characterize their physico-chemical properties, determine the directions of practical application. The literature data on ion transport in plasticized polymer membranes and theoretical aspects of membrane transport are critically reviewed. The eff ect of the modifi er on the transport properties of membranes is shown.

Approaches to the design of new hybrid polyoxaheterocyclic compounds based on the interaction of 2-(4-carboxybenzylidene)-3,4- dihydronaphthalene-1(2H)-one with methylene active compounds of the 2H-chromen-2-one series – 3 -(1,3-dioxobutan-1-yl)-2H-chromen2-one and 4-hydroxy-2H-chromen-2-one, as well as their carbocyclic analogue – 1,3-indanedione under various conditions have been considered.

In this work, the interaction of diarylmethylidene piperidones with acetylacetone and acetoacetic ester has been studied. It has been shown that the transition to piperidone in the basis of dienone does not allow the selective synthesis of products. It has been found that the direction of the reaction with 1,3-C,C-dinucleophilic reagents is infl uenced by the nature of peripheral ylidene substituents, which allows targeted synthesis of O-heterocyclization products (hexahydropyranopyridines) by introducing an NO2 group into the arylmethylidene fragment.