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51.
D. A. Usanov V. P. Meshchanov A. V. Skripal’ N. F. Popova D. V. Ponomarev M. K. Merdanov 《Technical Physics》2017,62(2):243-247
Novel, small-sized broadband matched loads in the form of disordered photonic crystals containing nanometer metallic and insulating layers have been developed. It has been proposed to form insulating layers with different permittivities and low dissipation factors in both centimeter and millimeter wavelength ranges from the composites that consist of insulating matrices filled with air inclusions. 相似文献
52.
John D. Spence Miranda L. Lackie Nicola A. Clayton Sergio A. Toscano Michelle A. Farmer Esfir Popova Marilyn M. Olmstead 《Tetrahedron letters》2014
Sonogashira coupling of buta-1,3-diynylbenzene with ((2-iodophenyl)ethynyl)trimethylsilane and 1,2-diiodobenzene led to the novel enetriyne, 1-ethynyl-2-(phenylbuta-1,3-diynyl)benzene, and enetetrayne, 1,2-bis(phenylbuta-1,3-diynyl)benzene, respectively. Solid state structural and thermal analyses are also described. In solution, 1-ethynyl-2-(phenylbuta-1,3-diynyl)benzene was found to undergo thermal Bergman cyclization to afford 2-(phenylethynyl)naphthalene. 相似文献
53.
54.
Popova E. V. Morozova P. V. Uspenskaya M. V. Radilov A. S. 《Russian Chemical Bulletin》2021,70(7):1335-1340
Russian Chemical Bulletin - An approach for the preparation of a polymer delivery system consisting of sodium alginate (SA) and carbopol was developed. The efficiency of the inclusion of medicinal... 相似文献
55.
In 2001, J.-M. Le Bars disproved the zero-one law (that says that every sentence from a certain logic is either true asymptotically almost surely (a.a.s.), or false a.a.s.) for existential monadic second order sentences (EMSO) on undirected graphs. He proved that there exists an EMSO sentence ? such that does not converge as (here, the probability distribution is uniform over the set of all graphs on the labeled set of vertices ). In the same paper, he conjectured that, for EMSO sentences with 2 first order variables, the zero-one law holds. In this paper, we disprove this conjecture. 相似文献
56.
A. V. Ivanova E. L. Gerasimova E. R. Gazizullina K. G. Popova A. I. Matern 《Journal of Analytical Chemistry》2017,72(4):415-420
Infusions of medicinal plants are investigated by potentiometry using a system of K3[Fe(CN)6]/K4[Fe(CN)6]. Models of some flavonoids, phenol carbonic acids, ascorbic acid, and their mixtures are studied. The total polyphenol concentration in these samples is determined by the Folin–Ciocalteu method. Dependences of antioxidant activity on extraction time are obtained. 相似文献
57.
V. E. Smirnova E. N. Popova V. M. Svetlichnyi L. A. Myagkova A. N. Orekhov V. E. Yudin A. M. Muzafarov E. A. Tatarinova 《Russian Journal of Applied Chemistry》2011,84(10):1800-1804
The effect exerted by thermal aging in air at 350°C on the thermal and mechanical properties of composite films prepared on
the basis of heat-resistant polyimide PM and non-film-forming polymethylphenylsiloxane (PMPS) was examined. The phase segregation
of polymeric composites of various compositions and the thermal aging rate were evaluated. 相似文献
58.
E. A. Ekimov S. G. Lyapin K. N. Boldyrev M. V. Kondrin R. Khmelnitskiy V. A. Gavva T. V. Kotereva M. N. Popova 《JETP Letters》2015,102(11):701-706
We report on the high-pressure synthesis of novel nano- and microcrystalline diamonds with germanium–vacancy (Ge–V) color centers emitting at 602 nm. The synthesis was carried out in non-metallic growth systems C–H–Ge and C–H–O–Ge enriched with germanium and carbon isotopes. We demonstrate germanium and carbon isotope shifts in the fine structure of the luminescence, which allows us to unambiguously associate the center with the germanium impurity entering into the diamond lattice. We show that there are two ground-state energy levels with the separation of 0.7 meV and two excited-state levels separated by 4.6 meV in the electronic structure of the center and suggest a split-vacancy structure of this center. High-intensity and narrow-line emission of high-pressure synthesized small diamonds with Ge–V centers makes them promising candidates for single-photon emitters. 相似文献
59.
60.
Mikolaichuk O. V. Protas A. V. Popova E. A. Molchanov O. E. Maistrenko D. N. Ostrovskii V. A. Pavlyukova Yu. N. Sharoyko V. V. Semenov K. N. 《Russian Journal of General Chemistry》2022,92(9):1621-1628
Russian Journal of General Chemistry - New tetrazole-containing derivatives of 2,4-diamino-1,3,5-triazine were synthesized. The cytotoxic activity of the obtained compounds against Huh-7 and HeLa... 相似文献