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141.
142.
Russian Chemical Bulletin - A convenient method for the synthesis of high-boiling-point α-(trifluoromethyl)styrenes was proposed. The regioselective synthesis of a series of ethyl...  相似文献   
143.
Ytterbium- and neodymium-substituted yttrium aluminum garnets were obtained by hydroxide coprecipitation and by the cryochemical method. A continuous series of solid solutions in the Y3Al5O12 — Yb3Al5O12 system and limited solid solutions (Nd x Y1 ? x )3Al5O12 (0 ≤ x ≤ 0.19) were obtained. The synthetic methods used made it possible to reduce the synthesis temperature from 1800 to 950°C and to obtain more homogeneous and nanosized material.  相似文献   
144.
Superconformal indices (SCIs) of 4d N = 4{{\mathcal N} = 4} SYM theories with simple gauge groups are described in terms of elliptic hypergeometric integrals. For F 4, E 6, E 7, E 8 gauge groups this yields first examples of integrals of such type. S-duality transformation for G 2 and F 4 SCIs is equivalent to a change of integration variables. Equality of SCIs for SP(2N) and SO(2N + 1) group theories is proved in several important special cases. Reduction of SCIs to partition functions of 3d N=2{{\mathcal N}=2} SYM theories with one matter field in the adjoint representation is investigated, corresponding 3d dual partners are found, and some new related hyperbolic beta integrals are conjectured.  相似文献   
145.
Russian Chemical Bulletin - A copper complex with N-(5,6-dihydro-4H-1,3-thiazin-2-yl)benzamide was synthesized for the first time and characterized by 1H NMR spectroscopy, LETDY mass spectrometry,...  相似文献   
146.
Relaxation processes in lead zirconate titanate after switching-off perturbations of different physical nature have been considered. The model of the process, which accounts for the partial depolarization during perturbations, the formation of charged F-centers during released charge trapping, and their relaxation, has been proposed.  相似文献   
147.
A novel technology for preparing nanocomposites on the basis of ultra-high-molecular-mass polyethylene and nanoparticles of inorganic compounds (SiO2, Al2O3, ZrO2, AlN, Si3N4) was developed and tested. The technology consists in liquid-phase compounding of nanocomposite components under the continuous action of ultrasonic vibrations. The developed technology ensures dispersion of nanopaticle agglomerates in a liquid medium, efficient mixing of components of the powder blend, and uniform distribution of nanoparticles in the polymer matrix. The nanocomposites obtained exhibit increased levels of strength and elasticity.  相似文献   
148.
Russian Chemical Bulletin - Ethyl α-nitro-β-trifluoromethyl acrylate was synthesized by nucleophile-catalyzed reaction of ethyl nitroacetate with excess trifluoroacetaldehyde methyl...  相似文献   
149.
Solubilities in the NaOH-TiO2 · H2O-H2O system at 25°C were studied. The solubility isotherm was found to have two maxima. The formation of two compounds, Na2Ti5O11 · 10H2O and Na2Ti3O7 · 7H2O, was established.  相似文献   
150.
We give a full list of known ${\mathcal{N}=1}$ supersymmetric quantum field theories related by the Seiberg electric-magnetic duality conjectures for SU(N), SP(2N) and G 2 gauge groups. Many of the presented dualities are new, not considered earlier in the literature. For all these theories we construct superconformal indices and express them in terms of elliptic hypergeometric integrals. This gives a systematic extension of the related R?melsberger and Dolan-Osborn results. Equality of indices in dual theories leads to various identities for elliptic hypergeometric integrals. About half of them were proven earlier, and another half represents new challenging conjectures. In particular, we conjecture a dozen new elliptic beta integrals on root systems extending the univariate elliptic beta integral discovered by the first author.  相似文献   
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