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101.
Fizer Oksana Fizer Maksym Sidey Vasyl 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):661-670
Journal of Radioanalytical and Nuclear Chemistry - The possibility of analytical determination of the uranyl cation UO22+ (taken in the form of the complex uranyl benzoate anion) by using the... 相似文献
102.
Bondarenko Marina Zaytseva Olga Trusova Valeriya Moiseenko Anton Rukin Aleksey Utytskykh Tetyana Morozova Oksana 《Journal of fluorescence》2021,31(4):1065-1073
Journal of Fluorescence - This study is devoted to the development of a methodological approach to mathematical analysis and data interpretation of blood serum phosphorescence intensity in cancer... 相似文献
103.
104.
Oksana Shishkina Stepan V. Lomov Ignaas Verpoest Larissa Gorbatikh 《Archive of Applied Mechanics (Ingenieur Archiv)》2014,84(6):789-805
In order to find an alternative core material to balsa wood in composite sandwich structures, it is important to understand balsa’s elastic properties in relation to its complex microstructural organisation. In the present work, experimental data on the elastic constants and microstructural features of balsa wood were collected for different porosities (densities) and processed into structure–property relations. An inverse problem was solved to predict variation of the cell wall properties with density, such that the collected experimental structure–property relations were satisfied. The Young’s modulus of the cell wall material in the longitudinal direction was found to increase with balsa’s density, which is consistent with the knowledge that the cell wall material stiffens during tree maturation. The value reported in the literature falls in the middle of the predicted range. The proposed micromechanical model also accurately calculated elastic properties of balsa wood at the mesolevel including longitudinal, radial, and tangential directions. The model took into account the presence of ray cells. It was shown that the addition of 15 % of rays increased the radial Young’s modulus up to 4 times with only slight decrease in the longitudinal modulus. 相似文献
105.
We consider finitely generated Lie superalgebras over a field of characteristic zero satisfying Capelli identities. We prove that any such an algebra with the maximality condition for abelian subalgebras is finite dimensional. In particular, any special Lie superalgebra with the maximality condition for its subalgebras has a finite dimension. We also prove that the universal enveloping algebra U(L) of special Lie superalgebra L is Noetherian if and only if $\dim L<\infty$ . 相似文献
106.
The co-presence of thiol vs. disulfide in the well-known Brust-Schiffrin two-phase synthesis has been identified as a source of size polydispersity in nanoparticles synthesized and a procedure has been proposed to address this long outstanding issue. 相似文献
107.
Mazurenko I Etienne M Ostermann R Smarsly BM Tananaiko O Zaitsev V Walcarius A 《Langmuir : the ACS journal of surfaces and colloids》2011,27(11):7140-7147
The modification of platinum nanofibers by silica using the electrochemically-assisted deposition is reported here. Pt nanofibers are obtained by electrospinning and deposited on a glass substrate. The electrochemically-assisted deposition of the sol-gel material then gives the unique possibility to finely tune the silica film thickness around these nanofibers. It also allows the successful encapsulation of a biomolecule (glucose oxidase was chosen here as a model) while retaining its biological activity, as pointed out via the electrochemical monitoring of H(2)O(2) produced upon addition of glucose in the medium. This silica-glucose oxidase composite offers the possibility of comparing systematically the influence of the deposition time on the bioelectrode response and to compare it with the particular features of the deposits. It was found that the film first grew uniformly around the nanofibers and then started to deposit between them, covering the whole sample (fibers and glass substrate), and tended to fully embed the nanofibers for prolonged deposition. The thickness of the silica film is critical for the electroactivity of the biocomposite, the best response being obtained for a silica layer thickness in the range of the fiber diameter (~50 nm). 相似文献
108.
Plekan O Cassidy A Balog R Jones NC Field D 《Physical chemistry chemical physics : PCCP》2012,14(28):9972-9976
A recent publication described a new group of spontaneously polarized materials in which electric fields in excess of 10(8) V m(-1) may be present. This phenomenon arises through dipole alignment in solid films formed by straightforward deposition from vapour and characterises a novel class of materials. Here we present further results for the properties of these materials, focusing on films of cis-methyl formate. These films are shown to display some notable new chemical physics. We find the novel result that the degree of dipole alignment and the corresponding electric field in films of cis-methyl formate can have a counter-intuitive temperature dependence, increasing six-fold between 80 K and 89 K, in sharp contrast to the pronounced and expected fall with deposition temperature seen both here between 50 K and 75 K and in numerous other species. A theoretical model demonstrates that the switch of gradient with rising temperature should be a general phenomenon and is associated with crossing of a singularity in the gradient occurring at a set of critical values of temperature and alignment. 相似文献
109.
110.
Myroslav Mykolayovych Sheremeta Yulia Vasylivna Stets Oksana Markiyanivna Sumyk 《Journal of Mathematical Sciences》2013,194(5):557-572
We study the Dirichlet series with an arbitrary abscissa of absolute convergence. The lower and upper estimates for sums of these series are found. The above results allow us to establish some relations between the maximum modulus and the maximal term of Dirichlet series, especially to find conditions that ensure that the maximum modulus and the maximal term have the same many-term asymptotics. 相似文献