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The array of rate constants (323 K) for the addition of peroxyl radicals of different structures to the π-bonds of unsaturated compounds was obtained. These data were analyzed using a combination of correlation and quantum chemical methods. The prospects of using Denisov's parabolic model are shown in comparison with classical linear correlations. It is noted that QSPR models using quantum chemical and structural descriptors can also be used to estimate the reactivity of reacting particles in this elementary act. The obtained kinetic information can be the basis for elucidating the detailed mechanism of oxidation of biologically significant molecules. [ABSTRACT FROM AUTHOR]

The rate constants and kinetic coefficients of inhibition (fkin) for olefins oxidized with the transition metal compounds (Mn) were measured by highly sensitive microvolumometry at 323 K in combination with kinetic modeling. The cyclic mechanism of the reactions of hydroxyl radicals with Mn leading to the multiple chain termination was confirmed as indicated by the observed effect of long-term inhibition of the oxidation of the substrates with Mn and obtained values of fkin > 102. [ABSTRACT FROM AUTHOR]

Highly sensitive microvolumometry at 323 K is used in combination with kinetic modeling to measure the rate constants (k4) and kinetic coefficients of inhibition (fkin) of the reaction of 1,4-substituted butadiene oxidation by hydroperoxyl radicals () in the presence of antioxidants (InH): 1,4-hydroquinone and 1,4-benzoquinone. The cyclic mechanism of interaction between and InH is confirmed: it leads to multiple chain termination, as is demonstrated by the observed long-term inhibition of the oxidation of substrates by hydroquinone and benzoquinone, and the obtained fkin > 102. It is shown that the drop in the value of k4 upon replacing –C6H5 substituent at the double bond in 1,4-substituted butadiene with –COOCH3 is due to the influence of specific solvation. [ABSTRACT FROM AUTHOR]

The results are presented of the major activities undertaken by the Geodynamic Research Centre during the final stage of Boguchanskaya hydroproject construction. [ABSTRACT FROM AUTHOR]

The results of experiments and computer simulations on the radical-chain oxidation of methyl linoleate in micelles are reported. The reaction rate constants included in the developed mathematical model are estimated. The ratio of the rates of first-order and bimolecular chain termination is examined. It is demonstrated that the rate constant of bimolecular chain termination in micelles is lower than that in the homogeneous phase. [ABSTRACT FROM AUTHOR]

We study the origin of the Higgs field in the framework of the universal extra dimensions. It is shown that a Higgs-like Lagrangian can be extracted from a metric of an extra space. The way to distinguish our model and the Standard Model is discussed. [ABSTRACT FROM AUTHOR]

We discuss the mechanisms of supermassive primordial black hole formation in the period before the beginning of star formation. We study the dependence of the primordial black hole mass spectrum on the initial conditions at the inflationary stage. [ABSTRACT FROM AUTHOR]

Amodified mechanism of the formation of large-scale antimatter regions is proposed. Antimatter appears owing to fluctuations of a complex scalar field that carries a baryon charge in the inflation era. [ABSTRACT FROM AUTHOR]

It is found that the main wear-prone elements in machines for firing pellets are the coolers; changing these requires stopping the machine every 70-90 days on average, interrupting the normal course of the technological process. Repairs revealed the efficiency of the guniting method for repair of linings of firing machines, in comparison with poured concrete. The lifetimes of gunite concrete linings were 2-3 times greater: 220-240 days. [ABSTRACT FROM AUTHOR]