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1.
Oleg Borodin 《Combinatorica》1993,13(1):121-125
The weight of an edge in a graph is the sum of the degrees of its end-vertices. It is proved that in each 3-polytope there exists either an edge of weight at most 13 for which both incident faces are triangles, or an edge of weight at most 10 which is incident with a triangle, or else an edge of weight at most 8. All the bounds 13, 10, and 8 are sharp and attained independently of each other. 相似文献
2.
I. P. Raevskii L. A. Reznichenko M. P. Ivliev V. G. Smotrakov V. V. Eremkin M. A. Malitskaya L. A. Shilkina S. I. Shevtsova A. V. Borodin 《Crystallography Reports》2003,48(3):486-490
(Na, K)NbO3 crystals with a perovskite structure and a KNbO3 content up to 40 mol % were grown from flux with the use of the solvent NaBO2. The dielectric measurements of the crystals grown revealed phase transitions that had never been observed before in ceramic samples. 相似文献
3.
A. N. Borodin 《Journal of Mathematical Sciences》1984,27(5):3005-3022
In this paper one considers methods which enable one to determine the distribution of certain functionals of a Brownian motion process. Among such functionals we have: the positive continuous additive functional of a Brownian motion, defined by the formula $$A\left( t \right) = \int\limits_{ - \infty }^\infty {\hat t\left( {t, y} \right)dF\left( y \right),} $$ where \(\hat t\left( {t, y} \right)\) is the Brownian local time process while F(y) is a monotonically increasing right continuous function; the functional $$B\left( t \right) = \mathop {\mathop \smallint \limits_{ - \infty } }\nolimits^\infty f\left( {y,\hat t\left( {t, y} \right)} \right)dy,$$ where f(y, x) is a continuous function; and the functional $$C\left( t \right) = \mathop {\mathop \smallint \limits_0 }\nolimits^t f\left( {w\left( s \right),\hat t\left( {sr} \right)} \right)ds$$ As an application of these methods one considers some concrete functionals such that \(\hat t^{ - 1} \left( z \right) = \min \left\{ {s:\hat t\left( {s, o} \right) = z} \right\},\mathop {\mathop \smallint \limits_{ - \infty } }\nolimits^\infty \hat t^2 \left( {t, y} \right)dy,\mathop {\sup }\limits_{y \in R^1 } \hat t\left( {T, y} \right)\) , where T is an exponential random time, independent of \(\hat t\left( {t, y} \right)\) . 相似文献
4.
We have conducted a high-level quantum chemistry study of the interactions of 1,2-dimethoxyethane (DME) with water for complexes representing both hydrophilic and hydrophobic hydration. It was found that our previous quantum chemistry-based force field for poly(ethylene oxide) (PEO) and its oligomers in aqueous solution did a poor job in describing the hydrophobic binding of water to the ether, consistent with our recent calculations of the excess free energy and entropy of hydration of DME. Our original force field was revised to more accurately reproduce the interaction of water with the carboneous portions of DME. Molecular dynamics simulations of aqueous DME solutions using the revised quantum chemistry-based potential yielded good agreement with experiment for excess free energy, enthalpy, and volume as well as excess solution viscosity and the self-diffusion of water. Comparison with our original potential revealed that the relatively hydrophobic ether-water interactions in the new potential strongly reduced the favorable excess free energy and enthalpy but have relatively little influence on the excess entropy for dilute DME solutions. Other properties of DME and PEO solutions including conformational populations and dynamics, solution viscosity, hydrogen bonding, water translational and rotational diffusion and neutron structure factor as a function of solution composition were found to be largely unchanged from those obtained using the original potential. 相似文献
5.
A. V. Mashkina V. R. Grunvald B. P. Borodin V. I. Nasteka V. N. Yakovleva L. N. Khairulina 《Reaction Kinetics and Catalysis Letters》1991,43(2):361-365
Na+/Al2O3 catalysts in disproportionation of methanethiol are highly selective towards dimethyl sulfide but less active compared to -Al2O3. Their activity falls with increasing Na+ in the sample. This decrease is due to the neutralization of Brönsted acid centers on the catalyst.
Na+/Al2O3 , , -Al2O3. Na+ . .相似文献
6.
7.
A. V. Mashkina V. R. Grunvald V. I. Nasteka B. P. Borodin V. N. Yakovleva L. N. Khairulina 《Reaction Kinetics and Catalysis Letters》1990,41(2):357-362
Disproportionation of thiol to sulfide and H2S takes place on catalysts of various composition, the most active being those with paired acid-base centers. On these catalysts at 200–400°C methanethiol is quantitatively converted to dimethyl sulfide. Disproportionation of ethanethiol and particularly of 2-propanethiol is accompanied by the decomposition of sulfides formed and initial thiols to produce olefins and H2S.
H2S , - . 200–400°C . 2- H2S.相似文献
8.
Tikhonov I. V. Pliss E. M. Borodin L. I. Sen’ V. D. 《Russian Chemical Bulletin》2016,65(12):2985-2987
Russian Chemical Bulletin - The kinetics of oxidation of methyl linoleate in micelles inhibited by stable nitroxyl radicals in the presence of superoxide dismutase was studied. In the presence of... 相似文献
9.
Putilin A. N. Morozov A. V. Kopenkin S. S. Dubynin S. E. Borodin Yu. P. 《Optics and Spectroscopy》2020,128(11):1828-1836
Optics and Spectroscopy - Main properties of holographic waveguide periscopic multiplexors of the exit pupil of optical systems of augmented reality displays are considered. Limitations in the... 相似文献
10.
V. A. Borodin T. A. Steriopolo V. A. Tatarchenko L. I. Chernyshova T. N. Yalovets 《Crystal Research and Technology》1985,20(2):159-166
The process of the Stepanov growth of sapphire tubes is studied at the growth rates up to 20 mm · min−1 in a Mo crucible with graphite succeptor. It is established that the main factor preventing the production of high-quality samples is contamination of the melt due to the gas transport reactions the growth chamber atmosphere and formation of oversaturated carbon solid solution in the Al2O3 matrix. The decomposition of this solid solution gives rise to the second-phase-particle precipitations. The production of highquality sapphire tubes at the growth rates up to 20 mm · min−1 is possible with a careful elimination of water vapours and oxygen from the growth chamber atmosphere. 相似文献