Vol. 49 No. 1 (236) (2015)

In this paper the densities of dimethylsulfone (DMSO2) solution in ethanol–water mixtures with various compositions have been measured over available concentration range (up to ~1 mol·kg^–1). Densities of solutions and apparent molar volumes were determined over 293.15–323.15 K temperature range. In DMSO2+ethanol–water systems the strongest interaction between ethanol and water molecules leads to the increase of partial molar volumes for DMSO2. It was shown that the competitive intermolecular interactions are responsible for the observed phenomena.

Impact of different factors (temperature, group separation, concentration) on volume properties of human hemoglobin (HHb) has been studied using densitometry method. Investigations were provided at temperatures 301.15, 309.75 and 313.15 K. It has been shown, that the densities, apparent partial specific volumes and partial specific volumes of HHb are different for separated and non-separated forms of HHb molecule.

Dependence of conductivity on temperature of sodium bis(2-ethylhexyl) sulfosuccinate (AOT)–n-heptane–water+dimethylsulfoxide (DMSO) or diethylsulfoxide (DESO) reverse micellar system has been studied at fixed ratio of molal concentrations of polar phase (water, water+DMSO, water+DESO) to surfactant and at different volume ratios of DMSO (DESO) and water. The threshold percolation temperatures (T_p) for each system have been estimated, the effects of both DMSO and DESO on threshold percolation temperature and percolation process have been discussed. Both DMSO and DESO act as percolation-resisting additives. The presence of mixed solvent has shown a decrease of T_p and tendency to transfer a system from percolating to non-percolating. The activation energy (E_p) for percolation of conductance has also been determined according to Arrhenius equation. The results show that E_p decreases with addition of DMSO or DESO and with an increase of concentration of DMSO.

The adsorption of anionic sodium dodecylsulfate (SDS) and cationic cetyltrimethylammonium bromide (CTAB) from aqueous solution on zealots was studied. A series of batch experiments were performed to determine the sorption isotherms of surfactants to zeolite. Furthermore, the isotherm parameters, average percentage errors were calculated. Other factors influencing the adsorption capacity (contact time, adsorbent amount, and initial surfactant concentration) were also discussed. The experimental data fitted very well to the Langmuir and Freundlich equilibrium models. Among the surfactants, CTAB showed higher adsorption capacity onto solid compared with SDS (284 and 113 respectively).

Sorption properties of sorbents on silica–manganese(II) oxide binary systems base have been evaluated by means of conductometry method. The influence of different factors (particularly the influence of pH values during the precipitation of manganese oxide and silica gel) on sorption properties of such systems has been discussed. The role of thermal treatment on sorption properties has been studied as well. It has been revealed that definite most optimal values for thermal treatment temperature exist, which lead to the sorbents characterized by higher adsorption capacity.

Interaction of urea with monomethylolurea and glyoxal has been investigated. The obtained products are forming the monomeryc and olygomeric complexes as well of chelate type by interaction with acetates of Ni²⁺ and Cu²⁺. The synthesized compounds have been studied by IR, PMR spectroscopy and elemental analysis.

In the article immobilization stress influence on leukopoiesis index, as well as on activity changes of proline biosynthesis enzymes on rabbit are studied. At the first stages of immobilization stress action increase of quantities of left bent neutrophilose nucleus and lymphocytes was observed, due to their quick access from bone marrow to peripheral blood: granulocytes bone marrow reserve, granulocytes bone marrow reserve, spleen and thymus lymphocytic cells stressor mobilization. Neutrophenia, eosynophenia and basophenia were also observed, during immobilization stress action duration increasing. Young and mature neutrophils quantity decrease has been observed in myelogram, that is the consequence of pressure proliferative and maturation processes of leukoblastic spire. Тhe highest enzyme activity in natural conditions was registered in liver and adrenal glands, whereas in conditions of immobilization stress the enzymes’ activities were changed and were detected in rabbit brain.

The melting of methylene blue (MB) complexes of DNA with different GC-content sequences at 0.02 M ionic strength of the solution has been carried out. It was shown that the change of melting interval width of MB complexes with DNA increases depending on GC-content enhancement within DNA sequences. It was revealed that MB is bound to DNA by semi-intercalation mode.

Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) are widespread mycotoxins with carcinogenic properties, contaminating feed and food. In this study the apoptosis-inducing effect of AFB1, OTA and ZEA combination at concentrations close to the natural contamination, in rat hepatocytes after 15, 30 and 60 days treatment in vivo is presented.

In the current study the influence of water and ethanolic extracts of plants on the concentration of glucose in human serum has been investigated. Plants growing both on soil and hydroponic have been investigated. The results show that ethanolic extracts decrease glucose concentration in human serum more in comparison with water extracts. It can be observed that ethanolic extracts of soil herbs and hydroponic plants influence on glucose concentration in the same way. The studies have been carried out in human serum in vitro.