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The paper deals with an urgent problem in the history of science, viz the mutual influence of natural philosophy and medicine in the 3^d century. At the end of the 2^nd and the beginning of the 3^d century, an important turn came about in medicine: the theory was formed which began to predominate in this field all over the civilized space – Galen’s anatomic-physiological system. Also, the paper analyses in detail the special role of Alexandrian school in the development of natural science: it ensured synergy of antique philosophy and Christian theology.

Denaturation of cellulosolytic enzymes produced by microorganisms Trichoderma viride in the presence of water was studied. Effective kinetic constants characterizing denaturation process were determined. It was shown that the enzymes in solution possess a narrow zone of stability, are stable at a temperature below 55 °С and rapidly gets denaturated when heated above 65 °С. In the dry state, the enzymes possess higher stability and get noticeably denaturated only at temperatures above 80 °С. The effective rate constant of denaturation is exponentially dependent on the concentration of water in the enzymatic preparation.

The interaction of amorphous silicon oxide (aerosil) with organic acids during mechanical activation in high-energy ball mill was studied by means of IR spectroscopy. It was demonstrated that monomer molecules of mono-, polyhydric and aromatic acids get bound with aerosil through the molecules of adsorbed water: aerosil–adsorbed water–acid. Water molecules form rather strong hydrogen bonds with the basic surface centres in aerosil and with hydroxyls of carboxylic groups in monomer molecules of acids. Both basic and acidic surface centres of the carrier take part in the mechanochemical interaction with aerosil.

UDC 541.18.053+543.42

Activated carbon was for the first time used as catalytic substrate in dechlorination process and a significant dechlorination (79 %) of most persistent 2,4,5–trichlorobiphenyl was achieved at 110 ºC in water/isopropanol solvent by applying reducing media. It was observed that carbon particles played a catalytic role to enhance the dechlorination process through substitution reactions and by suppressing further chlorination in reaction mixture. Dechlorination at the ortho position of biphenyl was clearly preceded through substitution reaction by hydroxyl and thiol ions. Moreover, in the absence of activated carbon, dechlorination was decreased and substituted products did not observed.

UDC 547

On the basis of the experimental data, a set of problems connected with the features of the crystallization of wavellite in the presence of additives is considered. It is established with the help of X-ray phase analysis that the precipitates formed under the conditions studied are presented by calcium oxalate monohydrate. The presence of magnesium ions, hydrophosphate, phosphate and sulphate ions in solution has an inhibiting action on the crystallization of calcium oxalate monohydrate. The hindering effect of the additive increases proportionally to an increase in the concentration of the additive. It was proved experimentally that amino acids have diverse effects on nucleation: some of them (glutamic acid, glycine, lysine etc.) inhibit the process, whereas the others (proline, alanine, valine etc.) act as catalysts; a number of amino acids (serine, phenylalanine) exhibit an insignificant effect on nucleation.

UDC 577.118.543.422

Alkaline hydrolyzates obtained from rice shuck processing were investigated. Results of the purification of alkaline hydrolyzates by means of coagulation, neutralization with the release of silicic acid, and sorption are presented. It is demonstrated that the purification methods used do not provide the requirements for preliminarily purified and fresh water for use in manufacturing unbleached cellulose with respect to the main hydrochemical parameters (coloration, mineralization, pH). It is established that alkaline hydrolyzates can be utilized with the formation of amorphous silicon dioxide which has a broad range of applications.

UDC 542.06:628.386:633.258

Data on the concentrations of hydrocarbons in the water phase and bottom settlings of sludge pits for the sludge pit technology of oil and gas well drilling are presented. Ionic and ultimate composition of the aqueous phase and bottom settlings were determined, as well as the concentration of radioactive elements. It was established that the high toxicity of sump hole content is mainly associated with the presence of high molecular fractions of hydrocarbons and the ions of sodium, potassium and chlorine. A substantial part of the sludge pit content is weakly toxic or non-toxic, it is confirmed by biotesting analysis. It is proposed to use the differentiated approach to the utilization of these wastes, in order to decrease material and energy expenses and increase the labour productivity.

UDC 504.064.47+504.054:622.816

Possibility of the low-temperature synthesis of zirconium dioxide nanopowder stabilized with yttrium (8 mol. %) from a mixture of hydrated zirconium oxynitride and yttrium carbonate mechanically activated in a continuous-type mill. It was shown that the powder formed even at 600 °С is easily moulded by dry pressing after disaggregation; its density after sintering is close to the theoretical value.

UDC 514.182+541.053

The composition of the soluble products of wheat straw delignification in the medium acetic acid–hydrogen peroxide–water–sulphuric acid catalyst was studied by means of elemental and chemical analysis, IR spectroscopy and gas chromatography-mass spectrometry. It was established that the vat residue formed in the regeneration of spent alkali liquor contains the products of polysaccharide degradation (4.7 rel. %), esters (19.9 rel. %) and sterols (37.2 rel. %). The acetic lignin precipitated from the alkali liquor contains a substantial amount of oxygen-containing functional groups. A promising character was demonstrated experimentally for the presently unclaimed bio-renewable resource such as wheat straw as a chemical raw material for obtaining sorbents and binders in the production of wood-based panels.

UDC 547.474:543.8:676.164

Selective sorption and desorption of the complex compounds of palladium from nitric solutions of silver on the ionites of different kinds was studied. Anionite VP-1P is recommended for the purification of electrolyte solutions from palladium in silver refining.

UDC 661.183: 669.23