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11.
I. V. Kalinovskaya V. G. Kuryavyi P. P. Safronov V. E. Karasev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(13):2173-2175
Mechanochemically synthesized europium nitrate with 1,10-phenanthroline (Phen) is formed into globules with sizes of 100–300
nm, which are assembled into larger globular aggregates or packed into layers. The increasing mechanical activation time induces
sintering, generating porous aggregates with micro-and nanopores. Eu2+ paramagnetic centers, detectable by ESR, are generated by mechanical grinding. Possibly, they are positioned on the surfaces
of nanoglobules. The complex Eu(NO3)3 · 2Phen synthesized conventionally from aqueous ethanol consists of needle-shaped microcrystallites. They do not give rise
to ESR spectra. 相似文献
12.
O. Safronov 《Journal of Functional Analysis》2008,255(3):755-767
We consider an elliptic random operator, which is the sum of the differential part and the potential. The potential considered in the paper is the same as the one in the Andersson model, however the differential part of the operator is different from the Laplace operator. We prove that such an operator has absolutely continuous spectrum on all of (0,∞). 相似文献
13.
A. A. Ostroushko M. O. Tonkushina A. P. Safronov A. E. Udilov 《Russian Journal of Inorganic Chemistry》2010,55(8):1260-1265
Molybdenum polyoxometalate buckyballs (NH4)42[MO72VIMO60VO372(ClCH2COO)30(H2O)72] · 250H2O · 15ClCH2COONa (Mo132Cl) were synthesized; some of their properties were studied, namely, purity, spectral and crystallographic parameters,
buckyball aggregation in solution, and interaction with water-soluble nonionic polymers (poly(vinyl alcohol) and poly(vinylpyrrolidone)).
The newly synthesized polyoxometalate was shown to have a lower stability than its analogue containing acetate instead of
chloroacetate groups, both having similar thermal destruction pathways. At the first heating steps, water is eliminated from
Mo132Cl. Thermal destruction at higher temperature produces chloroacetamide, chloroacetonitrile, and other compounds. 相似文献
14.
K. N. Gavrilov E. A. Rastorguev S. V. Zheglov N. N. Groshkin V. E. Boyko A. S. Safronov P. V. Petrovskii V. A. Davankov 《Russian Chemical Bulletin》2010,59(6):1242-1247
P,P-Bidentate diamidophosphite ligands containing the (3R,4R)-3,4-dioxy-1-(1-naphthyl)pyrrolidine-2,5-dione framework and 1,3,2-diazaphospholidine rings with the stereogenic P atoms
were obtained. The use of these ligands provides up to 85% ee in Pd-catalyzed asymmetric amination of (E)-1,3-diphenylallyl acetate and up to 95% ee in its asymmetric alkylation with dimethyl malonate. 相似文献
15.
A new concept of an X-ray brachytherapy setup based on the use of fluorescence from a secondary target placed at the tip of an implantable needle is proposed. Spatial dose-rate distributions for four combinations of secondary target materials and shapes are calculated by the Monte-Carlo method. 相似文献
16.
A. A. Ostroushko M. O. Tonkushina A. P. Safronov V. Yu. Korotaev V. A. Vazhenin V. Yu. Kolosov N. A. Martynova I. B. Kutyashev S. G. Bogdanov A. N. Pirogov K. B. Grzhegorzhevskii A. V. Prokof’eva 《Russian Journal of Inorganic Chemistry》2012,57(6):858-863
Samples of polyoxometalate Mo72Fe30: [Mo72Fe30O252(CH3COO)12{Mo2O7(H2O)}2 {H2Mo2O8(H2O)}(H2O)91] · ??150H2O with a buckyball structure, which can be both crystalline and amorphous, were synthesized. It was shown that such samples can be studied by neutron diffraction. The stability of Mo72Fe30 to heating and UV light exposure (in poly(vinyl alcohol) and polyvinylpyrrolidone films) was studied by IR, EPR, and electronic absorption spectroscopy; thermal analysis; and mass spectrometry. Mo72Fe30 was found to be less stable to heating and irradiation in a poly(vinyl alcohol) film as compared with the related polyoxometallate Mo132 free of iron. The sorption properties of Mo72Fe30 to organic vapors and its stability under sorption conditions were studied. It was demonstrated that, in addition to sorption, organic substances cause the destruction of buckyballs. 相似文献
17.
We consider the possibility of designing time-analyzing electron-optical systems for electron image tubes with subpicosecond
resolution, containing no spherical electrodes, fine-structure grids, or narrow slots (i.e., extremely simple systems with
high spatial and temporal resolutions). 相似文献
18.
Oleg Safronov 《Journal of Mathematical Analysis and Applications》2007,326(1):192-208
For a large class of multi-dimensional Schrödinger operators it is shown that the absolutely continuous spectrum is essentially supported by [0,∞). We require slow decay and mildly oscillatory behavior of the potential in a cone and can allow for arbitrary non-negative bounded potential outside the cone. In particular, we do not require the existence of wave operators. The result and method of proof extends previous work by Laptev, Naboko and Safronov. 相似文献
19.
E. G. Kalinina E. Yu. Pikalova V. D. Zhuravlev S. V. Scherbinin A. P. Safronov 《Russian Journal of Applied Chemistry》2017,90(6):862-869
Potentialities of the method of electrophoretic deposition of thin-film coatings based on micrometer powders of multidoped barium cerate BaCe0.8Sm0.19Cu0.01O3–δ (BCSCuO) and BaCe0.89Gd0.1Cu0.01O3–δ (BCGCuO) were considered. Micrometer powders of BCSCuO and BCGCuO were produced by the methods of solid-phase and citrate-nitrate syntheses, respectively. The dispersity, fraction composition, and electrokinetic potential of nonaqueous suspensions of these powders and the electrokinetic parameters of the electrophoretic deposition process were examined. An ultrasonic treatment and ultracentrifugation produced aggregatively stable suspensions of BCGCuO and BCSCuO micrometer particles in a mixed (70/30 vol %) isopropanol–acetyl acetone medium. These suspensions are characterized by high positive values of the zeta potential (+24 and +28 mV, respectively). Thin film coatings of the electrolyte materials BCSCuO and BCGCuO, which are of interest for the technology of medium-temperature solid-oxide fuel cells, were produced by the electrophoretic deposition onto a dense model cathode. 相似文献
20.
R. Gabbasov M. Polikarpov V. Safronov E. Sozontov A. Yurenya V. Panchenko 《Hyperfine Interactions》2016,237(1):34
In this work was proposed a new radiotherapy enhancement method consisting of the administration of magnetic nanoparticles into the cells with further irradiation with a gamma-ray beam. As a result, adjusting the energy distribution of a gamma-ray beam and 57Fe abundance it is possible to achieve an extremely intensive electron emission because of a nuclear resonance. The produced conversion and Auger electrons can be used as an effective tool for DNA lesions production. We developed a Monte Carlo model for an electron and gamma emission by 57Fe nucleus using the Geant4 program package. The parameters of a resonant absorption were taken from Mössbauer spectra of magnetite nanoparticles synthesized for the administration into live cells. The space distribution of the radiation dose showed an increase in the dose of 2–2.5 times in the case of the natural abundance and more than 50 times in the case of the 66 % enrichment of the nanoparticles. 相似文献