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41.
Monatshefte für Mathematik - For any polynomial $$P(x)in {mathbb {Z}}[x],$$ we study arithmetic dynamical systems generated by $$displaystyle {F_P(n)=mathop {prod nolimits _{kle... 相似文献
42.
Oleksiy O. Vakhnenko 《Letters in Mathematical Physics》2018,108(8):1807-1824
We suggest the six-component integrable nonlinear system on a quasi-one-dimensional lattice. Due to its symmetrical form, the general system permits a number of reductions; one of which treated as the semi-discrete integrable nonlinear Schrödinger system on a lattice with three structural elements in the unit cell is considered in considerable details. Besides six truly independent basic field variables, the system is characterized by four concomitant fields whose background values produce three additional types of inter-site resonant interactions between the basic fields. As a result, the system dynamics becomes associated with the highly nonstandard form of Poisson structure. The elementary Poisson brackets between all field variables are calculated and presented explicitly. The richness of system dynamics is demonstrated on the multi-component soliton solution written in terms of properly parameterized soliton characteristics. 相似文献
43.
[reaction: see text] The enhancing effect of several photosensitizers in photoinitiated radical carbonylation is demonstrated and applied to accelerate the synthesis of compounds labeled with short-lived 11C. With the sensitizers, the synthesis of [carbonyl-11C]esters and acids from alkyl iodides, [11C]carbon monoxide, alcohols, and water provided up to 75-85% decay-corrected radiochemical yields in 6-min reactions under mild conditions. Acetone was used as a sensitizer in preparing 13C-substituted 1,10-decanedicarboxylic acid from (13C)carbon monoxide. 相似文献
44.
Franois G. Chevallier Trevor J. Davies Oleksiy V. Klymenko Li Jiang Timothy G.J. Jones Richard G. Compton 《Journal of Electroanalytical Chemistry》2005,580(2):25
The cyclic voltammetric response of electrodes modified with catalytically reactive blocks is simulated using finite difference methods. The responses of three different models using various block geometries are studied. The results are used to determine kinetic parameters of coupled liquid|liquid interfacial reactions. First, we examine the liquid–liquid reaction between aqueous vitamin B12S and pure trans-dibromocyclohexane (DBCH) microdroplets immobilized on a basal plane pyrolytic graphite (bppg) surface, immersed in an aqueous solution of vitamin B12. Second, cyclic voltammetry on electrodes modified with microdroplets of DBCH diluted in dodecane is employed to determine the apparent bimolecular interfacial rate constant for the initial step in the DBCH(oil)/B12S(aq) reaction. The results are compared with a previous SECM/ITIES study of a similar reaction. 相似文献
45.
The connection between several hyperbolic type metrics is studied in subdomains of the Euclidean space. In particular, a new metric is introduced and compared to the distance ratio metric. 相似文献
46.
We obtain some refinements and extensions of the Basic Covering Theorem in a metric space (X, ρ). The properties of the metric ρ are used to define an inclusion coefficient k in this theorem, and this is related to the supremum of numbers t such that ρ
t
is a metric in X. The inclusion coefficient k characterizes ultrametric spaces. 相似文献
47.
48.
Oleksiy V. Klymenko Alexander I. Oleinick Irina Svir Christian Amatore 《Russian Journal of Electrochemistry》2012,48(6):593-599
In this paper we present a combined simulation approach for solving complex electrochemical kinetic problems at (hemi)spherical and (hemi)cylindrical electrodes based on the simultaneous application of analytical conformal coordinate transformations to accurately treat the diffusional transport and adaptive grid compression to locally increase the accuracy of the approximation of acute reaction fronts. This strategy is shown to be very efficient and leads to extremely accurate results both for steady state and transient situations and is equally powerful for both pure diffusion and that complicated by severe kinetic distortions. 相似文献
49.
The new strategy for adaptive simulation of electrochemical reaction mechanisms described in a previous paper (C. Amatore, O. Klymenko, I. Svir. Electrochem. Commun., (2010), doi:10.1016/j.elecom.2010.06.009) [1] provides an efficient method of obtaining accurate concentration distributions and electrochemical currents. In this paper, this strategy is illustrated and tested more deeply upon simulating several representative classical electrochemical mechanisms involving fast homogeneous comproportionation or disproportionation reactions that pose severe difficulties when simulated by classical finite difference methods including those based on exponentially expanding grids. 相似文献
50.
Sergey V. Kolotilov Oleksiy Shvets Natalia Kasian Lahcène Ouahab Vitaly V. Pavlishchuk 《Journal of solid state chemistry》2006,179(8):2426-2432
Porous magnetic composites were prepared by the synthesis of molecular sieve MCM-41 in the presence of Fe3O4 nanoparticles with average diameter of 15 nm. Nanoparticles were captured by porous silica matrix MCM-41, which resulted in their incorporation, as it was confirmed by TEM, SEM and X-ray diffraction. The materials possessed high surface area (392-666 m2 g−1), high pore volume (0.39-0.73 cm3 g−1) along with high magnetic response (MS up to 28.4 emu g−1 at 300 K). Calcination of samples resulted in partial oxidation of Fe3O4 to α-Fe2O3. The influence of nanoparticles content on sorption and magnetic properties of the composites was shown. No hysteresis was found for the samples at 300 K; at 5 K, HC was in the range 370-385 G for non-calcinated samples and 350-356 G for calcinated ones. 相似文献