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The collision of OH with the oxygen molecule is studied by the trajectory simulation technique on the model potential energy surface of OH + 0 2 -0 3 + H chemical reaction. Although the reaction channel is closed, we aim to demonstrate that the L-shape of the OH + 0 2 valley leads to the effective coupling of OH(v) vibration with the relative motion of collisional partners and therefore explains the high value of the vibrational relaxation rate constant observed experimentally. The characteristic feature of the mechanism considered is the predominance of one-quantum relaxation for low and multiquantum transitions for high OH vibrational levels. To estimate state-to-state vibrational relaxation rate constants, the method of dynamical corrections of transition state theory is used. The expression for the rate constant consists of a transition state term and a correction factor, determined in two-dimensional classical trajectory calculations. We also demonstrate the instability of motion on the potential energy surface with the L-shape valley, resulting from the scattering of the trajectory on the "comer" of the potential energy surface and the presence of regular and chaotic motions.

Polytetrafluoroethylene-based aerogel was synthesized for the first time. Graphene oxide was used as a binder. After reduction with hydrazine and annealing at 370 °C, the aerogel with a density of 29 ± 2 mg/cm3 became superhydrophobic. The aerogel was characterized by IR spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The sorption capacity of the aerogel for seven solvents and its sorption recyclability for hexane were measured.

Global properties of static, spherically symmetric configurations with scalar fields of sigma-model type with arbitrary potentials are studied in D dimensions, including models where the space-time contains multiple internal factor spaces. The latter are assumed to be Einstein spaces, not necessarily Ricci-flat, and the potential V includes contributions from their curvatures. The following results generalize those known in four dimensions: (A) a nohair theorem on the nonexistence, in case V ≥ 0 , of asymptotically flat black holes with varying scalar fields or moduli fields outside the event horizon; (B) nonexistence of particlelike solutions in field models with V ≥ 0 ; (C) nonexistence of wormhole solutions under very general conditions; (D) a restriction on possible global causal structures (represented by Carter-Penrose diagrams). The list of structures in all models under consideration is the same as is known for vacuum with a cosmological constant in general relativity: Minkowski (or AdS), Schwarzschild, de Sitter and Schwarzschild -de Sitter, and horizons which bound a static region are always simple. The results are applicable to various Kaluza-Klein, supergravity and stringy models with multiple dilaton and moduli fields.

The composite material was obtained by the polymerization of aniline in the presence of graphene oxide nanosheets (GONS). The resulting composite PANi (72%)-GONS (28%) was investigated by methods such as XPS, TGA, Raman and IR spectroscopy, and so on. It was established that a partial reduction of graphene oxide takes part in course of the polymerization. Specific capacitance of the PANi-GONS electrode in 1M H2SO4, corresponding to its discharge from 0.700 to 0.052 V, was found to be 547 F/g. But, if in the calculation of the capacitance include a shallow part of the discharge curve (below 0.15 V), one can obtain the value of specific capacity greater than 1200 F/g.

Processes induced by the heating of C 60 fullerite intercalated by oxygen are analyzed using mass-spectrometry, thermogravimetry, differential scanning calorimetry, and electronic spin resonance (ESR) techniques. It was found that the primary gas produced at the heating temperatures below 100 °C is molecular oxygen while at higher temperatures up to 200 °C carbon mono-and dioxides were also observed. The heating was accompanied by an appreciable increase in the ESR signal intensity. In order to gain insight into the oxidation products that are capable to contribute to the ESR signal, we performed all-electron density functional theory computations for C 58 O n (n ) 0-4), C 59 O n (n ) 0-2), and endohedral complexes O 2 @C 58 , O 2 @C 59 , and O 2 @C 60 . It is found that the triplet states of C 58 , C 58 O 3 , O 2 @C 58 O 2 , O 2 @C 58 , and O 2 @C 60 are lower in total energy than the corresponding triplet states. The singlet and triplet states of C 59 , O 2 @C 59 , and C 60 2are nearly degenerate in total energy. Thus, there are a number of species that can be responsible for the paramagnetic behavior observed in the oxidized fullerene.

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