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101.
102.
Artem M Abakumov Marina G Rozova Evgeny V Antipov Gustaaf Van Tendeloo 《Journal of solid state chemistry》2004,177(8):2855-2861
The new Pb5Sb2MnO11 compound was synthesized using a solid-state reaction in an evacuated sealed silica tube at 650°C. The crystal structure was determined ab initio using a combination of X-ray powder diffraction, electron diffraction and high-resolution electron microscopy (a=9.0660(8)Å, b=11.489(1)Å, c=10.9426(9)Å, S.G. Cmcm, RI=0.045, RP=0.059). The Pb5Sb2MnO11 crystal structure represents a new structure type and it can be considered as quasi-one-dimensional, built up of chains running along the c-axis and consisting of alternating Mn+2O7 capped trigonal prisms and Sb2O10 pairs of edge sharing Sb+5O6 octahedra. The chains are joined together by Pb atoms located between the chains. The Pb+2 cations have virtually identical coordination environments with a clear influence of the lone electron pair occupying one vertex of the PbO5E octahedra. Electronic structure calculations and electron localization function distribution analysis were performed to define the nature of the structural peculiarities. Pb5Sb2MnO11 exhibits paramagnetic behavior down to T=5 K with Weiss constant being nearly equal to zero that implies lack of cooperative magnetic interactions. 相似文献
103.
Varvara S. Stafeeva Alexander S. Mitiaev Artem M. Abakumov Alexander A. Tsirlin Artem M. Makarevich Evgeny V. Antipov 《Polyhedron》2007,26(18):5365-5369
Tin(II) acetate was prepared and its crystal structure was solved from X-ray powder diffraction data. Tin(II) acetate adopts a polymeric structure consisting of infinite Sn(CH3COO)2 chains running along the c-axis which are packed into groups of four. The acetate groups bridge the Sn atoms along the chains. The Sn atoms are asymmetrically surrounded by four oxygen atoms with two short Sn–O distances (2.170(6), 2.207(6) Å) and two longer ones (2.293(7), 2.372(8) Å). The coordination environment of the Sn atoms is completed up to a strongly distorted trigonal bipyramid SnO4E by the sterically active lone electron pair E. The coordination environment of the Sn atoms is virtually identical for Sn(CH3COO)2 in the gaseous and solid phase: the two short Sn–O bonds and the lone electron pair are located in the equatorial plane of the trigonal bipyramid and the two longer Sn–O bonds are directed towards the apical vertexes. Localization of the lone electron pair on Sn(II) was confirmed by electron localization function (ELF) analysis. The polymeric nature of the tin(II) acetate crystal structure was confirmed by a MALDI-TOF experiment. 相似文献
104.
I. N. Ivukin D. M. Artem’ev V. E. Bugrov M. A. Odnoblyudov A. E. Romanov 《Physics of the Solid State》2012,54(12):2421-2424
The stress-strain state in thin structured gallium nitride films on sapphire substrates containing open pores has been simulated. The results have been obtained by the finite element method in the commercial program complex. The stress intensity factor K I has been calculated for the model considering a crack at the GaN/sapphire interface near an open pore. Based on the calculations of elastic fields, the redistribution of stresses by a structure with an ordered array of open pores in gallium nitride films has been estimated. 相似文献
105.
Nataliya V. Slovesnova Artem S. Minin Anna V. Belousova Aleksey A. Ustyugov Kirill D. Chaprov Alexey P. Krinochkin Maria I. Valieva Yaroslav K. Shtaitz Ekaterina S. Starnovskaya Igor L. Nikonov Anton N. Tsmokalyuk Grigory A. Kim Sougata Santra Dmitry S. Kopchuk Emiliya V. Nosova Grigory V. Zyryanov 《Molecules (Basel, Switzerland)》2022,27(23)
Linked to Alzheimer’s disease (AD), amyloids and tau-protein are known to contain a large number of cysteine (Cys) residues. In addition, certain levels of some common biogenic thiols (cysteine (Cys), homocysteine (Hcy), glutathione (GSH), etc.) in biological fluids are closely related to AD as well as other diseases. Therefore, probes with a selective interaction with the above-mentioned thiols can be used for the monitoring and visualizing changes of (bio)thiols in the biological fluids as well as in the brain of animal models of Alzheimer’s disease. In this study, new Eu(III), Tb(III), Gd(III) and Sm(III) complexes of 2,2′-bipyridine ligands containing TEMPO fragments as receptor units for (bio)thiols are reported. The presence of free radical fragments of the ligand in the complexes was proved by using the electronic paramagnetic resonance (EPR) method. Among all the complexes, the Eu(III) complex turned out to be the most promising one as luminescence- and spin-probe for the detection of biogenic thiols. The EPR and fluorescent titration methods showed the interaction of the resulting complex with free Cys and GSH in solution. To study the practical applicability of the probes for the monitoring of AD in-vivo, by using the above-mentioned Eu(III)-based probe, the staining of the brain of mice with amyloidosis and Vero cell cultures supplemented with the cysteine-enriched medium was studied as well as the fluorescence titration of Bovine Serum Albumin, BSA (as the model for the thiol moieties containing protein), was carried out. Based on the results of fluorescence titration, the formation of a non-covalent inclusion complex between the above-mentioned Eu(III) complex and BSA was suggested. 相似文献
106.
107.
108.
Rodionova L. V. Shurygina I. A. Sukhov B. G. Popova L. G. Shurygin M. G. Artem’ev A. V. Pogodaeva N. N. Kuznetsov S. V. Gusarova N. K. Trofimov B. A. 《Russian Journal of General Chemistry》2015,85(2):485-487
Russian Journal of General Chemistry - Nanocomposite of heteropolysaccharide arabinogalactan and elemental selenium (0.54% of Se) has been prepared and studied by means of transmission electron... 相似文献
109.
Roustem D. Saiakhov Artem R. Cherkasov Alphia A. Shajmardanova Vladimir I. Galkin Rafael A. Cherkasov Paolo Finocchiaro 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1281-1289
Acid-base properties and reactivity of series of alpha-aminophosphonates has been investigated. The reaction of addition of the aminophosphonates to phenylisocyanate was used as a model reaction. The influence of steric and electronic effects of substituents at alpha-carbon or nitrogen in amino group on the mechanism inversion from AdN to AdE is discussed. 相似文献
110.