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81.
Tikhonov A. M. Asadchikov V. E. Volkov Yu. O. Roshchin B. S. Ermakov Yu. A. 《JETP Letters》2021,114(10):620-624
JETP Letters - The spectral properties of the correlation function of the heights of interlayer boundaries in a lamellar 1,2‑distearoyl-sn-glycero-3-phosphocholine film deposited on the... 相似文献
82.
Hybrid Silsesquioxane/Benzoate Cu7-Complexes: Synthesis,Unique Cage Structure,and Catalytic Activity
Alexey N. Bilyachenko Victor N. Khrustalev Evgenii I. Gutsul Anna Y. Zueva Alexander A. Korlyukov Lidia S. Shulpina Nikolay S. Ikonnikov Pavel V. Dorovatovskii Dmitri Gelman Elena S. Shubina Georgiy B. Shulpin 《Molecules (Basel, Switzerland)》2022,27(23)
A series of phenylsilsesquioxane-benzoate heptacopper complexes 1–3 were synthesized and characterized by X-ray crystallography. Two parallel routes of toluene spontaneous oxidation (into benzyl alcohol and benzoate) assisted the formation of the cagelike structure 1. A unique multi-ligation of copper ions (from (i) silsesquioxane, (ii) benzoate, (iii) benzyl alcohol, (iv) pyridine, (v) dimethyl-formamide and (vi) water ligands) was found in 1. Directed self-assembly using benzoic acid as a reactant afforded complexes 2–3 with the same main structural features as for 1, namely heptanuclear core coordinated by (i) two distorted pentameric cyclic silsesquioxane and (ii) four benzoate ligands, but featuring other solvate surroundings. Complex 3 was evaluated as a catalyst for the oxidation of alkanes to alkyl hydroperoxides and alcohols to ketones with hydrogen peroxide and tert-butyl hydroperoxide, respectively, at 50 °C in acetonitrile. The maximum yield of cyclohexane oxidation products as high as 32% was attained. The oxidation reaction results in a mixture of cyclohexyl hydroperoxide, cyclohexanol, and cyclohexanone. Upon the addition of triphenylphosphine, the cyclohexyl hydroperoxide is completely converted to cyclohexanol. The specific regio- and chemoselectivity in the oxidation of n-heptane and methylcyclohexane, respectively, indicate the involvement of of hydroxyl radicals. Complex 3 exhibits a high activity in the oxidation of alcohols. 相似文献
83.
S. Yu. Tikhonov 《Ukrainian Mathematical Journal》2005,57(3):517-522
We study classes of convex functions on (1, ∞] that tend to zero at infinity. Relations between different elements of these
classes are determined.
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Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 57, No. 3, pp. 427–431, March, 2005. 相似文献
84.
85.
V. V. Ptushenko L. N. Ikryannikova I. A. Grigor’ev I. A. Kirilyuk B. V. Trubitsin A. N. Tikhonov 《Applied magnetic resonance》2006,30(3-4):329-343
In this work, we investigated the interaction of a number of novel pH-sensitive spin probes (imidazoline- and imidazolidine-based nitroxides) with isolated chloroplasts. The light-induced changes in the electron paramagnetic resonance signals of these radicals are determined by several factors: ΔpH-driven accumulation of nitroxides inside the thylakoids, consumption (or evolution) of oxygen by chloroplasts, and irreversible loss of spin probe paramagnetism. A comparative study of these radicals characterized by different pKa allowed us to conclude that these spin probes can be used as pH indicators for monitoring the intrathylakoid pH- and light-induced changes in oxygen concentration in chloroplast suspension. 相似文献
86.
A. V. Vershubskii V. I. Priklonskii A. N. Tikhonov 《Russian Journal of General Chemistry》2007,77(11):2027-2039
Results of simulation of electron and proton transport in higher plant chloroplasts, taking into account the lateral heterogeneity of their lamellar system, were summarized. The existence of heterogeneous lateral profiles of pH inside thylakoids and in gaps between the thylakoids of grana was predicted. The basic kinetic relationships were simulated for photoinduced redox transformations of P700, the primary electron donor for PS1. It was shown that, along with changes in pH inside thylakoids, an essential role in controlling the electron transport in chloroplasts can belong to alkalinization of the gap between thylakoids of grana, caused by deceleration of diffusion of hydrogen ions from the stroma to the PS2 complexes in thylakoids of grana. 相似文献
87.
A. Kovarski T. Yushkina V. Kasparov A. Shapiro A. Tikhonov 《Colloid and polymer science》2003,281(4):308-318
88.
89.
90.
In this paper, we discuss a model of emissivity of snow cover taking into account its structure. We assume that upward and
downward radiation inside a snow layer are diffuse and apply the two-flux theory of Kubelka and Munk. Snow cover is modelled
by a medium comprising discrete scatterers. In the case of dry snow, the scatterers are ice grains. Wet snow is modelled by
a mixture of ice grains (with or without water envelopes) and water drops. We assume that the scatterers are spherical particles
that have lognormal distribution over size. The brightness temperature of radio emission from snow cover on the soil is calculated
using the data of glaciological measurements of physical parameters and microstructure of snow. Results of calculations are
compared to measurements of the brightness temperature of radio emission from various types of snow covers.
Space Research Institute of Russian Academy of Sciences, Moscow, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii,
Radiofizika, Vol. 42, No. 9, pp. 845–857, August 1999. 相似文献