The Software System LingvoDoc and the Possibilities It Offers for Documentation and Analysis of Ob-Ugric Languages

Doklady Mathematics - The LingvoDoc system ( http://lingvodoc.ispras.ru ) provides a service for collaborative language documentation and computations on the collected data. This software system...     

Copper(II) and nickel(II) complexes with bis(azomethine)—a condensation product of 1-phenyl-3-methyl-4-formyl-5-mercaptopyrazole with 1,3-diaminopropan-2-ol

The copper(II) and nickel(II) complexes based on bis(azomethine), which is the condensation product of 1-phenyl-3-methyl-4-formyl-5-mercaptopyrazole with 1,3-diaminopropan-2-ol, are synthesized. Bis-azomethines can form both binuclear and mononuclear complexes in which the hydroxy group is not involved in coordination. The binuclear copper(II) complexes with the acetate and pyrazolate bridges exhibit an antiferromagnetic exchange, which strength is determined by the nature of the bridge (2J = ?154 and ?424 cm^?1, respectively). The structure parameters of the coordination spheres of the complexes are determined by X-ray absorption spectroscopy. The structure of the CHCl₃ solvate of the binuclear copper(II) complex with the pyrazolate bridge is solved by X-ray diffraction analysis (CIF file CCDC 964655).     

Binuclear complexes of copper(II) with 1′-phthalazinylhydrazones of substituted salicylic aldehydes: Physico-chemical study and quantum-chemical simulation

Binuclear complexes of copper(II) with 1′-phthalazinylhydrazones of substituted salicylic aldehydes have been prepared and studied. Antiferromagnetic exchange interaction between copper(II) ions has been revealed in all the complexes. Taking advantage of quantum-chemical simulation, we have investigated the influence of the complexes structural isomerism on the character of the exchange interaction between the paramagnetic centers. X-ray absorbance spectroscopy afforded the structural parameters of coordination spheres of copper(II) ions; it has been demonstrated that dimerization occurred via the nitrogen atoms of phthalazine fragments.     

Study of the Process $${e}^{{+}}{e}^{{-}}{\to}{\eta\pi}^{{0}}{\gamma}$$ in the Cossision-Energy Range of $$\sqrt{{s}}{=}{1.05{-}2.00}$$ GeV

Physics of Atomic Nuclei - The process $$e^{+}e^{-}\to\eta\pi^{0}\gamma$$ is studied in the range of center-of-mass (c.m.) collision energies between 1.05 and 2.00 GeV on the basis of data...     

Measurement of the Cross Section for the Process $${e^{+}e^{-}}{\to}{K}^{{+}}{K}^{{-}}{\pi}^{{0}}$$ with the SND Detector at Collision Energies of $$\sqrt{{s}}{=}{1.3{-}2.0}$$ GeV in the Center-of-Mass Frame

Physics of Atomic Nuclei - In an experiment with the SND detector at the VEPP-2000 $$e^{+}e^{-}$$ collider, the cross sections for the processes $$e^{+}e^{-}\to K^{+}K^{-}\pi^{0}$$ and...     

Erratum to: The Software System LingvoDoc and the Possibilities It Offers for Documentation and Analysis of Ob-Ugric Languages

Doklady Mathematics - An Erratum to this paper has been published: https://doi.org/10.1134/S1064562422340038     

Measurement of the relative probability of the decay φ → η′γ in the channel η′ → ηπ0π0, η → γγ

The process e ⁺ e ^? → η′γ, η′ → η π⁰π⁰, η → γγ is investigated by an SND detector in experiment on a VEPP-2M equipment with colliding electron-positron beams. The analysis of experimental data yields a value of B(? → η′γ)=(6.7 _?4.2 ^+5.0 ±1.5)×10^?5 for the decay probability. Taking into account a previous measurement of this quantity by an SND detector in the decay channel η′ → π⁺π^?η, one finally obtains B(?→η ′γ)=(6.7 _?2.4 ^+2.8 ±0.8)×10^?5.     

Transport properties of granular metals at low temperatures

We investigate transport in a granular metallic system at large tunneling conductance between the grains, g(T)>1. We show that at low temperatures, Tg(T)delta) behavior where conductivity is controlled by the scales of the order of the grain size. In three dimensions we predict the metal-insulator transition at the bare tunneling conductance g(C)(T)=(1/6pi)ln((E(C)/delta), where E(C) is the charging energy of a single grain. Corrections to the density of states of granular metals due to the electron-electron interaction are calculated. Our results compare favorably with the logarithmic dependence of resistivity in the high-T(c) cuprate superconductors indicating that these materials may have a granular structure.     

Searching for the process e+e- → K+K-π0 in experiments with the spherical neutral detector at VEPP-2M

We have searched for the process e⁺e^- → K⁺K^-π⁰ at energies up to 1.38 GeVin an experiment with the spherical neutral detector at the VEPP-2M e⁺e^- collider. The upper limits of the cross sections for the processes σ(e⁺e →; φπ: → K⁺K^-π⁰) < 0.023 nb and σ(e⁺e^- → KK*(892) → K⁺K^-π⁰) < 0.059 nb have been established at a 95% confidence level.     

Three ABTS<Superscript>•+</Superscript> radical cation-based approaches for the evaluation of antioxidant activity: fast- and slow-reacting antioxidant behavior

This work focuses on the behavior and comparative assessment of the antioxidant activity of several well-known antioxidants using three different approaches with the same ABTS^?+/potassium persulfate radical-generating system: a decolorization assay, kinetic assay, and visual-spectrophotometric titration assay. The decolorization assay is the most common approach but gives little information on antioxidant behavior. The kinetic assay can be used for an in-depth study of the specific features of a particular antioxidant and facilitates identification of the mechanism of action. The visual-spectrophotometric titration assay is complementary to the above assays and subdivided into two stages to demonstrate the contribution of the “fast” and “slow” scavenging properties to the total antioxidant activity. The trolox equivalent antioxidant capacity (TEAC) value ranges for several flavonoids and the endogenous antioxidants derived from these assays vary from 0.7 to 5.1, 0.5–2.8, and 0.4–3.7, respectively, while the sequence of the weakest antioxidant to the strongest is similar. The analysis of the kinetic curves for some flavonoids showed that their interaction with ABTS^?+ has an atypical character. Based on the results of the kinetic and visual-spectrophotometric titration assays, fast-reacting (trolox, α-tocopherol), slow-reacting (naringenin, apigenin) and moderate-reacting antioxidant (dihydroquercetin, quercetin, rutin, morin, and glutathione) compounds were distinguished.