Composites based on calcium phosphates in the matrix of biopolymer (citrated plasma and fibrin) were synthesized in neutral and alkaline medium. At pH 7 brushite composites were obtained, whereas at pH 11 amorphized hydroxyapatite was precipitated. Disruption of precipitation conditions led to the formation of tricalcium phosphate impurity, which was detected by XRD after thermal treatment of composites at 800 °C. Composition and morphology of calcium phosphates did not depend on biopolymer nature. To determine bioactivity degree, composites were incubated in model Simulated Body Fluid (SBF) for 75 days. It was found that composites based on amorphized hydroxyapatite incorporated in biopolymer matrix have maximum growth of biomimetic layer of apatite.

Interfacial interactions of cationic surfactants of various chemical structures at the solution / finely dispersed mineral material (quartz and dolomite) interface were studied. It is established that the modification of the surfaces of quartz and dolomite with cationic surfactants leads to a change in the structure and radius of the capillaries due to the formation of adsorption-solvate shells. The hydrophobic ability of cationic surfactants is determined by the structure of the hydrophilic part of their molecules – the balance of amino groups in the alkyl chains and the absence of steric hindrances during adsorption interaction with the surface of mineral materials. The mixture of surfactants containing six amino groups and a polyhydric alcohol glycerin has an effective hydrophobic ability from both aqueous and highly mineralized solutions.

At a temperature of 20 ± 1 °C, the distribution of model substances of various classes of organic non-electrolytes in n-hexane – aqueous solutions of dipotassium phosphate and potassium acetate was studied. The increments of the methylene and functional groups of organic non-electrolytes are calculated. It has been shown that in case of dipotassium phosphate, the nature of the salting out effect is enhancing the structure of the salt solution and the growth of the methylene group increment. For potassium acetate, the increment of the methylene group slightly increases with increasing salt concentration, and for most functional groups it increases significantly. An explanation of the dependences of the increment values on the nature and composition of the salt solution is given.

The object of the study was a polymeric biocidal material – polyhexamethyleneguanidine hydrochloride (PGMG GC). The purpose of this work was to develop a method for the quantitative determination of HMDA in the target synthesis product – PGMG GC by high-performance liquid chromatography (HPLC). Analytical data obtained during the assessment of the system’s precision, specificity, precision, accuracy and linearity of the method corresponded to the established acceptance criteria. The proposed analytical method of HMDA determination in polymeric PGMG GC is validated with respect to the indicated parameters and can be used to determine the HMDA content in the range 0,75–0,025 %.

In order to therapeutically destroy cancer neoplasms, chemotherapy or radiotherapy are commonly used. In the isotope medicine, however, medical isotopes of the short-lived radionuclides are injected into the tumor (⁵⁹Fe, ⁹⁰Y, ⁹⁵Zr, ^99mTc, ¹⁰⁶Ru, ^114*In, ¹⁴⁷Eu, ¹⁴⁸Eu, ¹⁵⁵Eu, ¹⁷⁰Tm, ¹⁸⁸Re, ²¹⁰Po, ²²²Rn, ²³⁰U, ²³⁷Pu, ²⁴⁰Cm, ²⁴¹Cm, ²⁵³Es). Binary, or neutroncapturing, technology is a technology developed for the selective effect on malignant tumors and using a tropic to tumors preparations containing non-radioactive nuclides (¹⁰B, ¹¹³Cd, ¹⁵⁷Gd et. al.). Triadic technology is a sequential administration of a combination of two or more separately inactive and harmless components tropic to tumor tissues that can selectively accumulate in them or react with each other to destroy tumors under certain external impacts. The aim of this work is the quantum-chemical modeling of the electronic structure and the analysis of the thermodynamic stability of the new methotrexate containing nanoscale fullerenolic radionuclide tumor-fghting agents. The need for preliminary studies on modeling of such objects is caused by the very high labor intensity, cost and complexity of their practical preparation.

A convenient three-step method for synthesis of heptyl (4-trifluoroacetyl)benzoate, an important neutral anion carrier, has been developed. The key step of the method is acylation of toluene by trifluoroacetic anhydride in presence of aluminium chloride at –8 – –10 ^oC. The procedure gives high overall yield and, unlike the earlier methods, does not include any organometallic reagents, therefore allowing scaling it up to several hundred grams, that makes the target compound much more readily available.

A one-step method for the transformation of 3α,5-cyclo-6β-methyl ethers of steroids into the corresponding 3α,5-cyclo-6-ketones under the action of methyl (trifluoromethyl) dioxirane has been developed. The possibilities of the method have been demonstrated by preparing 3-dehydrotesterone, the biosynthetic precursor of brassinolide.

Growth hormone (GH) is a polypeptide produced in the anterior pituitary lobe that triggers different biochemical pathways and increases cell proliferation and growth. In this work, the pNic based vector for periplasmatic secretion was developed. Recombinant human growth hormone was produced via periplasmatic secretion (42h, 30 °С) followed by several steps of purification. GH obtained does not contain His-tag. Expression level of 2,85 mg per1 literof bacterial culture was achieved.

A method for hydrogels production by the formation of cross-linked binary polymer complexes is proposed. Necessary conditions for synthesis were determined, providing a high degree of swelling of hydroaccumulating polymeric materials based on anionic copolymers of acrylamide and polyacrylic acid. Chemical interaction of components of polymer complex has been proved by the methods of infrared spectroscopy and potentiometric titration. The possibility of moisture absorption control of hydrogels depending on synthesis conditions and application purpose was shown.

A new catalyst for green Suzuki–Miyaura cross-coupling and Mott-Schottky nitrobenzene reduction processes was prepared by thermolysis of palladium (II) poly-5-vinyltetrazolate. Heterogeneous catalyst includes Pd-nanoparticles supported on polymeric matrix. It presents recoverable and recyclable catalyst and the catalyzed reactions proceed in aqueous media at room temperature in aerobic conditions.

According to the years of research, maps of pre-Chernobyl background radiation and radon volumetric activity in buildings within theterritoryofBelaruswere constructed. For the first time the comparison of the listed maps was carried out.

Effect of the soil temperature on concentration and total reserve of cadmium, lead and uranium in the interstitial (pore) water of (0–20)-cm samples of sod-podzolic soil with moisture content of 60 % of the water capacity (WC) after their keeping at the definite temperature (in the range of 14–40 °С) was established. It was found that character and extent to which temperature effects on concentration and total reserve of every heavy metal (Cd, Pb, U) in the soil pore solution depended on the chemical nature of heavy metal and peculiarities of soil. In the temperature range of 14–40 °С and moisture content in the soil samples 60 % of the WC, portions of the cadmium, lead and uranium in the soil pore solution decreased in the following way: a_Cd (0.2–0.4 %) > a_Pb (0.06–0.07 %) > a_U (0.03–0.04 %). The concentrations and total reserves of cadmium, lead and uranium in the soil pore solution increased with lowering the temperature and it was especially true in regard to cadmium. The 5 °С temperature decrease in the range of 14–40 °С caused the content of cadmium in the soil pore solution to increase an average of 25 %, lead – 5.2 and U – 4.6 %. The iron content in the soil solution also increased with decreasing temperature, which indicated a decrease in the sorption capacity of iron hydroxides present in the soil, which probably played a prominent role in fixing cadmium, lead and uranium in the soil studied.

Complex research of the most important physico-chemical and mechanical properties (granulometric composition, hygroscopicity, caking, dusting, compactability, friability) of model system based on potassium sulfate and experimental samples of potassium sulfate and potassium-magnesia has been conducted. The experimental samples of potassium sulphate and potassium-magnesia were obtained in the processing of polymineral ore in the presence of various amounts of impurity inorganic salts (magnesium sulfate and chloride, sodium chloride). The obtained chlorine-free fertilizers have low hygroscopicity and low caking, but they are characterized by high dusting. Studies of the influence of dust-suppressors of different chemical nature on dusting of model and experimental samples of potassium sulfate and potassium-magnesia have shown that polyethylene glycol PEG-400 has the highest dust suppression effect on these fertilizers. Using PEG-400 has no negative influence to the friability, caking and compactability of fertilizers.

Optimization of the liquid-phase oxidation of α-pinene was carried out using the Box plan. It was found that an increase in the temperature of the oxidation process in the interval 55–85 °C leads to an increase in the amount of polymers from 45 to 55 %, and a decrease in the air flow rate from 1000 to 600 ml/min – to a 10 % decrease in terpenic oxygencontaining compounds (verbenol, verbenon, epoxy α-pinene). Increasing the duration of oxidation from 5 to 15 h leads to a reduction in the content of α-pinene from 70 to 48 %, which indicates its high conversion. The results of the experimental plan have been processed, the optimum process conditions found, which ensure the maximum yield terpenic oxygencontaining compounds and a high conversion α-pinene with the minimum content of polymers in the oxidation products, have been calculated and confirmed in practice. It was established that at a temperature of 70–75 °C, an air flow rate of 1000 ml/min and an oxidation time of 5 h, the quantitative content of the main products was: terpenic oxygen-containing compounds – 27.04 %, monomers – 69.70 %, polymers – 30.30 %.

This article shows the possibility of using the method of self-propagating high-temperature synthesis to obtain protective and hardening coatings for the lining of various thermal installations. The development of compositions of ceramic masses for the production of SHS coatings was carried out on the basis of aluminum powder, clay raw materials, exhausting and fluxing components as well as mineralizing additives. The prepared suspension including pre-prepared and thoroughly mixed raw materials was applied with a brush or a spray gun onto the previously cleaned and moistened surface of an aluminosilicate refractory. The firing of the coating was carried out in accordance with the mode of removing the thermal unit at the operating temperature. The temperature of the initiation of the SHS process, previously established using differential thermal analysis, was in the range of 570–720 °C and depended on the chemical composition of the charge. It has been established that the presence of crystalline phases of silica, corundum, hematite and a number of solid solutions (mainly calcium and sodium aluminosilicates) in the coating structure provides the necessary combination of the thermomechanical and thermophysical characteristics of the coatings. On the basis of the conducted research, the expediency of applying the technology of self-propagating high-temperature synthesis for the production of protective and hardening coatings on the lining of thermal units is demonstrated, which is confirmed by industrial tests in the conditions of the Minsk Ceramic Factory OJSC «Keramin».

The possibility of purification of circulating solutions containing triethanolamine from CaCl₂ impurities by introducing into them potassium carbonate is shown. This process procceds according to the reaction K₂CO₃ + CaCl₂ → ↓CaCO₃ + 2KCl. The influence of the consumption rate of potassium carbonate has been studied. It is shown that at the stoichiometric consumption rate of K₂CO₃, the content of Ca²⁺ ions in the liquid phase was 0,02 %, while with a K₂CO₃ deficiency of the stoichiometric consumption rate of 70 and 50 %, this value was 0,43 and 0,92 %, respectively. It has been established that the circulating solutions purified from CaCl₂ can be used in the conversion of new portions of KCl and phosphogypsum.