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Synthesis of grafted copolymers of sodium lignosulfonate with methyl acrylate was performed by means of radical (co)polymerization. Mechanism of grafted radical (co)polymerization was proposed on the basis of IR spectroscopy data and functional analysis. Polyelectrolyte, hydrodynamic, polymolecular, and surfactant properties of water-soluble grafted copolymers were studied.

Gas chromatography—mass spectrometry was used to study the component composition of extractives of normal and rotten aspen wood. The pathogen activates enzymatic oxidative processes, which increase the content of polyunsaturated fatty acids in the lipid fraction.

The effect of the solvent composition in the binary mixtures of water with dimethyl sulfoxide, acetonitrile and 1,4-dioxane on the positions of absorption bands in the UV spectra of five guaiacylic phenols, as well as of the corresponding phenolate anions, simulating structural units of natural lignin macromolecules, was studied. The data obtained were interpreted based on the model of a stepwise solvent exchange in the solvation shells. Parameters of a preferential solvation and compositions of solvation shells of lignin related phenols were calculated. A determining role of water complexes with aprotic solvents in the solvation equilibria involving phenols under study was shown.

A liquid chromatography–tandem mass spectrometry method is proposed for the simultaneous determination of 1,1-dimethylhydrazine, methylhydrazine, N,N-dimethylformamide, 1-methyl-1H-1,2,4-triazole, dimethylguanidine, N-nitrosodimethylamine and 1,1,4,4-tetramethyltetrazene, important rocket fuel pollutants of soils. Chromatographic separation was conducted according to previously published results in an isocratic mode on an analytical column with a Nucleosil-100–5SA sulfo-cation-exchanger. The mobile phase composition was optimised in order to achieve effective separation of all analytes and provide high sensitivity of mass spectrometric detection – an ammonium acetate buffer solution (50 mM, pH 5.4) containing methanol (25%) was used. Detection was performed in the positive electrospray ionisation mode with multiple reaction monitoring (MRM). The parameters of ion source, ion optics, the inlet potentials of the quadrupoles and the collision energy for the detection of the found product ions were optimised....

The physicochemical properties of slightly altered dioxane lignins isolated from Juniperus communis wood of different ages were studied. It was shown that the functional nature and reactivity of the lignins changed during lignification of the wood.

The amino-acid composition and total nitrogen content in 25 samples of four commercial Arctic brown algae Saccharina latissima (L.) C. E. Lane, C. Mayes, Druehl & G. W. Saunders; Laminaria digitata (Hudson) J. V. Lamouroux; Fucus vesiculosus (L.); and Ascophyllum nodosum (L.) Le Jolis were studied. The use of brown algae not only as raw material for producing mono- and polysaccharides but also as a source for obtaining amino acids for the production of drugs and functional foods was recommended. Factors for calculating total nitrogen in protein that differed from the commonly accepted ones were proposed.

Kuznetsova I., Bogolitsyn K., larionov n., Boytsova t., Palamarchuk I., aksenov a.: structure and physical–chemical properties of humic acids of oligotrophic peat bog of arkhangelsk region. Ekologia (Bratislava), vol. 33, no. 1, p. 1–8, 2014. The article presents data on the elemental and functional composition of humic acids, their molecular weight characteristics, physical, chemical and acid–base properties. The sorption properties of humic acids towards cd2+ and Pb2+ are studied. The relationship between the polyelectrolyte nature of humic acids and their sorption capacity is revealed.

The possibility of cellulose diacetate production by direct acetylation of sulfite pulp with acetic anhydride in supercritical carbon dioxide (SC CO2) is demonstrated. Optimum acetic anhydride to cellulose ratio and parameters of SC CO2 are selected.

Supercritical fluid extraction of a highly toxic rocket-fuel component (1,1-dimethylhydrazine, UDMH) from peaty soils with carbon dioxide is proposed as a rapid method of sample preparation for ion-chromatographic analysis. Optimum conditions of extraction have been determined. The efficiency of the UDMH extraction can be improved by basic treatments of the soil sample and by the use of proper additives to SC CO2 (cosolvents).

The ultramicroscopic composition and supramolecular structure of wood matrix were investigated by methods of electron and atomic force microscopy (AFM). New data on specific features of the composition and cell wall structure of Juniper wood (Juniperus communis L.) were obtained. Native lignin was found to be water soluble. It was also shown that lignin does not constitute a continuous matrix between cellulose fibrils, but is deposited as spherical particles.

Peroxide delignification of cellulose fibers in acid medium in presence of polyoxometalates as catalysts was studied. The effects of the hydrogen peroxide concentration, the catalyst nature, and the addition of the alkali processing stage on the process of delignification of leafy and coniferous celluloses were investigated.

Acid dissociation constants for three main types of phenol structural fragments of lignin in binary mixtures of water with N,N-dymethylformamide, dimethyl sulfoxide, and 1,4-dioxane were determined by spectrophotometric potentiometric titration. The effect of solvent on lignin protolytic properties was examined on the basis of the Kamlet-Taft principle of linear relationship of free solvation energies. It was found that nonspecific interactions with solvent make the dominating contribution to the effect of the medium.

Multiparameter regression analysis combined with the principle of liner solvation energies relationship was applied to assess the solvent effect on the acidity of the lignin-related phenols in water-dioxane and water-acetone systems. The coefficients a, b, and s of the Kamlet-Taft equation were calculated taking into account the contributions of different types of solute-solvent interactions to the protolytic properties of the phenols of the guaiacol series.

The features of the interaction in a system biocomposite (peat)-solvent (H2O, 0.1 M NaOH, C2H5OH) have been considered. The enthalpies of interaction have been calculated, and the kinetic dependencies of changes in enthalpy characteristics in processes accompanied by the extraction of peat components have been obtained.

A comprehensive characterization study was carried out for liquid, gaseous, and solid wastes generated by two pulp and paper mills in Northwest Russia. An environmental impact assessment method based on the technical standards set for discharges (emissions) of priority pollutants was tested for individual process units and the entire enterprise.

The leachate generated by the solid domestic waste landfill in the city of Arkhangel’sk affects the natural waters of the swamp in the landfill location site. Based on the results from laboratory studies, the main pollutants brought by the landfill leachate were identified and quantitatively determined, and the environmental condition of the area adjacent to the landfill was characterized. The pollutant migration routes were determined. The contribution of the landfill leachate to the chemical composition of the natural environment components in the adjacent swamplands was determined, and the impact it exerts on the environmental condition of the area surveyed was assessed.

Changes in the content of lignin functional groups during low-temperature delignification under the action of hydrogen peroxide in supercritical (SC) CO2 in the preparation of fibrous cellulose half-finished product were considered. The action of the oxidizer caused changes in the molecular weight characteristics of lignins. The experimental data showed the occurrence of both oxidation and substitution processes. Oxidation in SC CO2 resulted in the formation of water- and alkali-soluble medium- and low-oxidized lignins because of decreased oxidizer consumption.

The influence of the launch of carrier rockets of different classes on chemical composition of the air in the working zone of the Plesetsk Cosmodrome is studied by ion chromatography, spectrophotometry, and gas analysis. On the basis of analysis of data obtained, the efficiency of methods used and the locality and short-term duration of atmospheric pollution by toxic components of rocket propellants in the region of the launch complex at the cosmodrome are deduced.

The influence of pressure on the parameters of low-temperature oxidative delignification of firry wood in supercritical carbon dioxide under the action of hydrogen peroxide is described. The chemical composition of the cellulose half-finished products is characterized.

The acid-base properties of dioxane lignins from the roseroot stonecrop (Rhodiola rosea L.) and the saw-wort (Serratula coronata L.) have been studied by spectrophotometrically determining the ionization constants for phenol hydroxyl groups. A correlation between the molecular masses of the fractions of lignins and their acid-base properties has been established.

The published information on the use of enzymes belonging to a large family of peroxidases of plant and fungal origin as the catalysts of lignin and its model compound oxidation by hydrogen peroxide are reviewed. The structures and the mechanism of the catalytic action of these enzymes are comparatively considered. The enzymes have similar structures; however, the enzymes of plant origin have higher stabilities and pH optima. It was concluded that further studies of the effect of the functional nature, polymolecular properties, and regularities of the redox conversions during the catalytic oxidation of plant lignins by plant peroxidases are promising.

The kinetics of catalytic oxidation for ferulic acid with polyoxometalates used as catalysts was studied. The effect of pH and concentrations of the principal reacting components on the process kinetics was studied. A kinetic scheme of oxidation is proposed, and the values of a number of kinetic parameters of the process are determined.

A kinetic scheme was suggested for the oxidation of guaiacol, ferulic acid, acetovanilon, and vanillyl alcohol with hydrogen peroxide. A number of kinetic parameters were determined.

Characteristic IR and UV absorption bands, as well as oxidation half-wave potential on a platinum disc electrode in the cyclic mode were determined for the low-temperature hydrophilic ionic liquid 1-butyl-3-methylimidazolium acetate. Temperature dependences of the refractive index, density, and ansolute viscosity were determined in the temperature range 298–328 K. The activation energy of viscous flow was calculated.

The pKa values were determined for 10 guaiacyl phenols by UV spectrophotometric and potentiometric titration in the water—dioxane binary system over the composition range 0–80% organic solvent. The differentiating action of the solvent and para-substituent effects on the acidity of guaiacol derivatives were analyzed. The dependences of acidity constants on the mixed solvent composition were interpreted using the preferential solvation model.

The influence of the composition of the water-N,N-dimethylformamide mixed solvent on the position of the B absorption band in UV spectra of 2-methoxyphenol, its para-substituted derivatives, and corresponding phenolate anions simulating base units of natural lignin is investigated. The data obtained are interpreted in terms of the model of preferential solvation. The preferential solvation parameters and compositions of the solvation shells are calculated.

Northern wetlands ecosystems play an important role in the hydrological balance of neighboring areas, where they act as chemical barriers against anthropogenic and technogenic contaminations. Studied region is well known for quantity of peat deposits and the volume of peat resources. Peat can be considered as a highly informative marker for assessing change in environmental conditions. The study presents the results of the first investigation of peat samples, collected from representative ecosystems of northern wetland territories with low anthropogenic impact. Component and element composition of various peat types were studied in a relation to hydrologic, climate and sampling conditions. It was found out that organic and ash contents are more dependent on the type of the bog, than geographic location. Climatic factors are more important for the formation of bitumen. The degradation degree in peat increases proportionally to content of humates. High content of biogenic and lithogenic elements was observed in transition- and low-moor peat. The content of trace elements in peat samples do not depend on the type of the peat. The structural properties of peat were studied by the light microscopy, AFM and dynamic light scattering. It was determined that the conformation of studied peat samples is characterized by elements of asymmetry. The observed particles in the solutions exist in dynamic equilibrium with separated globular macromolecules. The size of these nanoparticles is comparable with the size of the particles of other biopolymers of similar nature. Swelling of peat in liquid water was studied. The relationship between structural specificities, origin of peat and its maximum degree of swelling was found. The degree of swelling can be used as structural-sensitive parameter in further research.

Acid ionization constants of the phenolic hydroxy groups of guaiacol derivatives in water-acetone mixtures were determined. The acidity of these phenols was analyzed in relation to both the acetone content in the mixed solvent and kind of para-substituent.

Reference no. 13 should read: 13. O. S. Brovko, I. A. Palamarchuk, T. A. Boitsova, et al., Macromol. Res. 23, 1057 (2015).

It is shown that cellulose can be acetylated with acetic anhydride in supercritical carbon dioxide in the absence of traditional catalysts, toxic solvents, and dilutants. As substrates, three cellulose samples were tested: sulfite and sulfate cellulose and cellulose obtained by low-temperature delignification in a supercritical carbon dioxide medium. The chemical composition of the cellulose diacetate product is characterized.

The investigations confirm the physicochemical nature of the structure and self-assembly of wood substance and endorse its application in plant species. The characteristic morphological features, ultra-microstructure, and submolecular structure of coniferous wood matrix using junipers as the representative tree were investigated by scanning electron (SEM) and atomic-force microscopy (AFM). Novel results on the specific composition and cell wall structure features of the common juniper (Juniperus Communis L.) were obtained. These data confirm the possibility of considering the wood substance as a nanobiocomposite. The cellulose nanofibrils (20–50 nm) and globular-shaped lignin–carbohydrate structures (diameter of 5–60 nm) form the base of such a nanobiocomposite.

The rheological properties of sodium alginate solutions were studied as influenced by the concentration of alginic acid, pH of the medium, and temperature. The probable structural and conformational transformations induced on varying these parameters were suggested. The effect of cations and anions of varied nature on the viscous characteristics of these solutions was discussed.

Interaction of lignin with dimethyl formamide, dimethyl sulfoxide, and dioxane was studied by calorimetry. Concentration dependences of the enthalpy of interaction between lignin and aprotic solvents were obtained.

The first part of this investigation studied complex nature of chemical oxygen demand (COD ) parameter on local and overall effluents, which were obtained from two pulp and paper mills, located in the Northwest region of Russia. Contribution of individual compounds and fractions of matters having different chemical nature to COD for these effluents was established. The second part of this study shows that, qualitative and quantitative characteristics of priority pollutants and their contribution to COD for different pulp and paper mills are not the same, though these mills use similar technologies and produce similar products.

The kinetics of oxidation of vanadyl acetylacetonate to VO(OH)(OMe)(acac) by molecular O2 in MeOH have been studied spectrophotometrically. The reaction, which is pseudo first-order with respect to [VO(acac)2] and [O2], is inhibited by Hacac and a vanadium(V) complex. The rate data were used to calculate the thermodynamic activation parameters. A mechanism for the reaction is discussed.

The kinetics of the reduction of octacyanometallates(IV) in alkaline aqueous medium have been studied spectrophotometrically. The experimental results are in agreement with following rate law:-d[M(CN) inf8 sup3− ]/dt = k obs[M(CN) inf8 sup3− ]2[OH−][Na+] where k obs = 4.1 × 10−2M−3s−1 (Mo) and 4.0 × 10−4 M−3 s−1 (W). The rate data were used to calculate the thermodynamic activation parameters ΔH ‡ and ΔS ‡. A mechanism of the reaction is discussed.

The thermodynamic miscibility of lignin, hemicellulose and cellulose has been investigated by the common solvent vapour static sorption method. This has allowed determination of the changes of free energy of the polymer mixing. Experimental results allow confirmation that the leading role of hemicellulose as a binder between cellulose and lignin microfields in the cell wall is not only in formation of covalent and hydrogen bonds, but also in formation of solid solutions with other components in transition layers. The physicochemical model of wood matrix formation was suggested on the basis of interconnection of changes in functional composition, redox properties and the thermodynamic state of biopolymers.