Vol. 35 No. 1 (194) (2001)

The influence of H₂SO₄ additions to micellar water–dioxane mixtures of E-30 on Ph₂ NH+K₂S₂O₈ reaction rate is studied. It is shown that in tne initial stage H₂SO₄ additions to water–1,4 dioxane E-30 micellar solutions they have almost no influence on the reaction rate. Only 160 min after the start of the reaction its rate begins to increase.

An interaction of palladium (II) anionic complex with dye of acridine row rivanol has been studied. Formed compound could be extracted by iso-amylacetate. Maximal extinction for dye aqueous solutions and for extracts of compound and “blind” extracts as well is observed at the same value of wavelength is 365 nm. Under optimal acidity conditions (pH 2 by sulphuric acid) palladium (II) is extracted practically quantitatively (R = 88.5%) during 1 min shaking. The optimal quantities of potassium iodide and dye are correspondingly 0.6 mL of 1·10^–2 mol/L and 0.6 mL of 0.05% solutions. The iso-amylacetic extracts of coloured ionic associate are submitted to the main low of spectrophotometry in the 0.3–3.8 mcg/mL range of palladium (II) contents. Effective coefficient of molar extinction equals to 1.8·10^–4 cm^–1. The molar ratio between palladium (II) iodide complex and rivanol in forming compound has been determined, which is 1:1. The influence of interfering and accompanying elements on the determination of palladium using rivanol has been studied. Extraction-absorbtiometric methods elaborated have been applied for determination of palladium in various samples of catalysts of organic synthesis.

Summary Kinetics of the reactions acrylonitrile (AN)–secondary amine [piperidine (PP), morpholine (Mph), diethylamine (DEA), dipropylamine (DPA) and dietanolamine (DEolA)] has been studied in aqueous solutions and water–1,4-dioxane mixtures, using UV-spectroscopic and dilatometric methods at 298 K. It has been shown, that for all studied couples the reaction law is: W = K[AN] [Amine]. A correlation between reactions’ rate constants and the product of ionization potential (I) with amine’s basicity (pK_b) has been established. It has been shown, that with increase of water fraction in water–1,4-dioxane mixtures the rate of AN–secondary amine reaction increases. Influence of medium on the AN–secondary amine reaction rate, taking into account medium viscosity, dielectric constant, refraction index, electrophility and nucleophility of water and 1,4-dioxane has been discussed.

It is studied that the TSK influence of cumene, CHP and OS-20 on initiation on the quickness of oxidation rate of reactions is studied. It is shown that in any case TSK displays an inhibitorating character. Kinetic parameters characterizing the inhibitor are measured. During the oxidation of cumene in the reaction RO₂ + In→ROOH +In the temperature dependence of velocity constant is determined as: k₇ = 4.49·10⁸ exp(-5300/RT) L/mol·s.

Maximum positive ellipticity parameter’s values were received for rat liver chromatin preparations in control and under in vivo and in vitro actions of steroid hormone hydrocortisone and peptide hormone insulin. It was shown, that in vivo action of both hormones lead to significant increase of this parameter’s value. In vitro action of hormones doesn’t changee the value of the mentioned parameter of hormones doesn’t reveal additivity. Specific antagonism of hydrocortisone and insulin action at chromatin is observed. It is noteworthy that a change of the parameter’s value of the maximum positive ellipticity is observed in total chromatin preparations as well as in its active fraction.

Influence of the hippocamp on the system of hemocoagulation was investigated. It was revealed that the low-frequency electrostimulation of hippocamp leads to hipocoagulating changes of studied biochemical exponents of blood coagulation, which is supposed to be the result of inhibitory influence of hippocamp.

Investigation of antioxidant properties of some herbs was carried out. Efficiency of herbs as antioxidants was tested by the influence of their extracts on the intensity of spontaneous chemiluminescence and by the change of the level of the malonic dialdehyde in the model system. The obtained results indicate that all experimented extracts show antioxidant properties in different degrees.

The effect of temperature on conformation and catalytic activity of bovine liver arginase in aqueous solutions was studied. During the experiment ([Ca]=4.2·I0^–7M, pH 9.5) under the influence of the temperature of 60–80℃ the inactivation of the arginase was accompanied by a decrease of Michaelis constant values and reduction of triptophane fluroscence. In the presence of ornithine the sensitiveness of the enzyme towards the temperature effect is considerably increased. The results led to the conclusion that the thermic inactivation of arginase in a solution is a result of the violation of native conformational condition, not directly affecting the active center of the enzyme. The measuring of intensity of triptophane fluroscence can be successfully used to registrate conformational changes in arginase solutions under existing conditions.

Activity of enzymes of different samples of the virgin, weakly and powerful cultivated rock semi-desert and brown soils was investigated. It is stated that the ecological factors, which determine the soils' biological activity, are changed during the soils' cultivation. It may be proved by the enzyme activity determination. During soils' cultivation the activity of enzymes is submitted to regular changing, hence it may be used as an exponent of the level of soils' cultivation.

It has been shown that photocyclization N-benzylamide acetoacetic acid in present three-ethanolamine or anhydryde acetic acid gives 2-oxo-4-methyl-5-phenyl-Δ³-pyrrolin. The formal kinetics of the process is given.

A method for chromatographic separation and quantitative determination of mixture of nine alyphatic mono-atomic alcohols for educational purposes corresponding to the "Methods of chromatographic analysis" program for university chemical departments has been elaborated. The analysis has been carried out on LXM-72 chromatograph with flameionization detector and temperature programming. The conditions and regime of chromatography process have been justified. Duration of analyses is 25 min. Volume of analysing sample is 1 mkL.

Study of changes of free proline content in connection with organ formation processes of two potato sorts has shown that these processes are accompanied by the increase of free proline content in all organs of plants within different quantitative limits. The comparison of sensability of various organs of potato to the break of organism equalized state has shown the significant differences between organs of both middle and late ripe sorts. When transition to the tuberization took place the free proline content reached its maximum in stolons for both sorts, especially for the late ripe sort. This fact indicates that among all organs the stolons are the most sensible to the break of equalized state.