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Isolation of artemisinin from Artemisia annua L. and its quantification by the HPLC-MS method are considered. Different extraction methods were used for the isolation of artemisinin: maceration, ultrasonic and subcritical CO2-extraction. The component content of the CO2- and hexane extracts was studied by the GC-MS method.

Lipids in the colloidal (micellar) form were isolated from sapropel of a lake of Karasevoe (Tomsk region) using the method of aqueous vibromagnetic extraction. It has been demonstrated that the yield of lipids in the vibromagnetic treatment of sapropel increases, and in the aqueous extract it is comparable to the yield of lipids isolated using organic solvents. The concentration of fatty acids in the studied samples was qualitatively and quantitatively evaluated by chromatography-mass spectrometry. It has been demonstrated that the total concentration of saturated and unsaturated fatty acids in the products of vibromagnetic treatment increases. The dispersion of sapropel particles has been demonstrated by scanning electron microscopy.

Aqueous vibromagnetic extraction of hydrophobic and hydrophilic biologically active substances from peloids of varied origin (sapropels, and sulfide-slime mud) was developed. Instrumental analytical techniques (GC/MS, TLS, IR spectroscopy), gravimetry, and other methods were used to determine polar and nonpolar lipids and saturated and unsaturated fatty carboxylic and humic acids in colloid systems.

The Chernobyl accident resulted in environmental radionuclide pollution in many areas, including the Dnepr river. The water and fish of the Kakhovsk Water Reservoir were under study and tested for 90Sr and 137Cs. It was found that the content of 137Cs achieved pre-accident levels and that of 90Sr was 4-6 times higher than that prior to the accident. The fish levels of the above radionuclides were 10-20 times as high as the pre-accident levels. Due to the consumption of fish, the radiation doses of the radionuclides, mainly 90Sr, in the population living in the costal areas of the Kakhovsk Water Reservoir were 20-30 times higher than the pre-accident levels.

Carbonyl compounds in the form of 2,4-dinitrophenylhydrazones in alcoholic solutions were analyzed by high-performance liquid chromatography. This simple procedure is characterized by high sensitivity and reproducibility.

1. The integral enthalpies of dissolution of 100% nitric acid in concentrated aqueous solutions of sulfuric acid\( - \Delta H_{HNO_3 } \) were measured calorimetrically at 298°K; when the concentration of H2SO4 was changed from 90.90 to 99.48% with\(C_{HNO_3 } \) = 0.1 mole/liter,\(\Delta H_{HNO_3 } \) changed from −4.4 to −8.4 kcal/mole. 2. The heat of dilution of the sulfuric acid makes the basic contribution to the value of the integral heat of dissolution of 100% nitric acid in concentrated aqueous solutions of sulfuric acid. 3. The value of the enthalpy of ionization of nitric acid in concentrated aqueous solutions of sulfuric acid (\(\Delta H_{HNO_2 } + _{ + HSO_4 } - \))was determined. The value of\(\Delta H_{HNO_2 } + _{ + HSO_4 } - \) with\(C_{HNO_3 } \) = 0.1 mole/liter decreased from 1.7 kcal/mole in 90.90% sulfuric acid to −0.3 to −0,5 kcal/mole in 99.48% sulfuric acid. 4. In the starting 99.48% and 98.44% sulfuric acid, the values of\(\Delta H_{HNO_2 } + _{ + HSO_4 } - \)were almost independent of the concentration of nitric acid with concentrations of the acid of 0.05 to 1 mole/liter.

A system of parameters for the calculation of standard enthalpies of formation of organic compounds has been developed. The system is based on group increments. It has been shown during the calculation of enthalpy of formation of polyfunctional compounds that in order to obtain accuracy close to the experimental value it is necessary to introduce corrections accounting for the interaction between the functional groups.

A system of parameters was developed which permits estimating the heat capacity of liquid organic compounds at different temperatures based on the temperature dependence of the group contributions.

The possible mechanisms for the cis-trans isomerization of nitrostilbenes in the presence of aromatic amines were discussed and it was shown that the reason for the isomerization is the formation of charge-transfer complexes.

From a computer analysis of the numerical values of molar volume and density of a wide range of organic compounds a system of parameters has been developed that is based on the contributions of groups of atoms (a scheme that takes immediate environment into account). For multifunctional compounds it is necessary to introduce additional corrections that reflect interactions between groups.

1. A study was carried out on the effect of chloro and nitro derivatives of methane on the nature and quantitative indices of the nitration of cellulose by nitric acid. 2. The use of mixtures of HNO3 and an organic solvent gives rapid nitration of cellulose as a consequence both of the high rate of diffusion of these mixtures into the interior of the cellulose fiber and with structural transformations during nitration.

1. The esterification of cellulose is achieved with greatest efficiency relative to reaction time and nitrogen content in the products in a mixture containing 80% HNO3, 15% H3PO4, and 5% H2O. 2. The esterification of cellulose in this mixture proceeds under milder conditions and with a lower heat effect than upon using 100% HNO3 or HNO3-H2SO4, mixtures.