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81.
82.
We report the first experimental observation of impulse confinement and the disintegration of shock and solitary waves in one-dimensional strongly nonlinear composite granular materials. The chains consist of alternating ensembles of beads with high and low elastic moduli (more than 2 orders of magnitude difference) of different masses. The trapped energy is contained within the "softer" sections of the composite chain and is slowly released in the form of weak, separated pulses over an extended period of time. This effect is enhanced by using a specific group assembly and precompression. 相似文献
83.
Olga B. Nesterenko 《Journal of Mathematical Sciences》2013,190(4):606-612
The conditions of existence of the unique solution of a boundary-value problem for weakly nonlinear integro-differential equations with parameters and the equivalence of such problem and the appropriate integral equation are established. 相似文献
84.
85.
Kvasil J. Nesterenko V. O. Kleinig W. Boẑik D. Reinhard P. -G. Lo Iudice N. 《The European Physical Journal A - Hadrons and Nuclei》2013,49(9):1-13
All transfer reactions and radiative capture nuclear-astrophysical reactions at low energies measured so far are analysed using a reaction theory that contains overlap functions between the wave functions of the target and residual nuclei. These overlaps are assumed to have an asymptotic form determined by the separation energy of the transferred (or radiative captured) cluster and such an assumption is incorporated into all reaction codes. We point out that although this asymptotic form is dominant for the majority of the transfer reactions and the nuclear-astrophysical radiative capture reactions, for some cases the overlap function has anomalous asymptotic behavior. This behavior originates from virtual decays of the complex nucleus into intermediate channels and, mathematically, is generated by contributions from the singularities of the triangle Feynman diagram and the generalised triangle diagram containing a loop. In the present work, these contributions are investigated in detail and expressions are derived for the strengths of the anomalous terms taking spin variables and the Coulomb effects into account. We present specific examples of nuclear vertices with anomalous asymptotics and discuss their application for peripheral nuclear processes. 相似文献
86.
A. S. Sidorkin L. P. Nesterenko A. L. Smirnov G. L. Smirnov S. V. Ryabtsev A. A. Sidorkin 《Physics of the Solid State》2008,50(11):2157-2163
The fatigue of lead titanate and lead zirconate titanate ferroelectric thin films, i.e., a change in the polarization as a function of the number of switching cycles in an external electric field, is investigated experimentally. The threshold numbers of switching cycles are determined to be 1010–1011 for the lead titanate films and 109–1010 for the lead zirconate titanate films. It is shown that a change in the temperature does not substantially affect the threshold number of switching cycles at which the switched polarization decreases drastically. However, an increase in the external field strength leads to a noticeable decrease in the threshold number of switching cycles. The process of fatigue is accompanied by an increase in the coercive field and the internal bias field. It is established that, as the number of switching cycles increases, the internal bias field changes more significantly as compared to the coercive field. The absence of a change in the phase composition in repeatedly switched samples indicates that the fatigue processes have a nonchemical nature. The anomaly observed in the frequency dependence of the permittivity in the frequency range 106–107 Hz due to the domain structure disappears after multiple switching cycles. This suggests that the observed fatigue phenomenon has a domain nature. 相似文献
87.
This paper details a study of the selectivity characteristics of high-performance chelation ion chromatography when separating a range of metal ions with a number of complexing eluents. It shows that exploitation of competitive metal complexation between ligands in the eluent and surface bonded chelating groups allows a wide range of control over the retention order and selectivity coefficients of groups of metal ions for specific applications. An indication of the metal separation characteristics found for simple non-complexing eluents on iminodiacetic acid (IDA) silica bonded substrates is given first, followed by an illustration of the selectivity changes that can be achieved by using complexing eluents. Using a novel approach, plots of logbeta(1) of the metal complexes of a chosen eluent ligand against the surface bonded IDA metal complexes were found to be useful indicators of which metals may show unusual selectivity changes during separation. Example chromatograms of metal separations are given for three selected complexing eluent reagents, namely, oxalic acid, picolinic acid, and chloride, either singly or in admixture. For special mention it was found that very specific retention control could be achieved for Cu(II) with picolinic acid, Fe(III) and Fe(II) speciation with oxalic acid, Pb with dipicolinic acid and Cd with chloride. 相似文献
88.
Palchaudhuri R Nesterenko V Hergenrother PJ 《Journal of the American Chemical Society》2008,130(31):10274-10281
Compounds incorporating the triphenylmethyl motif constitute an emerging family of potent anticancer agents. Although several small molecules containing this pharmacophore have now been identified, the mechanism of cell death induction for some of these compounds is unknown. In an effort to define their mechanism of action, and to distinguish subtypes within the group of compounds containing the triphenylmethyl moiety, we have created novel triphenylmethyl-containing small molecules and have evaluated them in a battery of biological assays. Here we show that several phosphonate and phosphonochloridates possessing the triphenylmethyl motif potently induce death of multiple cancer cell lines in culture. Further assays evaluating the ability to cause cell cycle arrest, inhibit tubulin polymerization, dissociate mitochondrial-bound hexokinase in cancer cells, and inhibit calcium-dependent potassium ion channels indicate that triphenylmethyl-containing compounds can be placed into at least four distinct categories, each with a different mechanism of action. 相似文献
89.
Hypercrosslinked polystyrene, first introduced by Davankov and Tsyurupa, is obtained by an extensive crosslinking of polystyrene (or styrene-divinylbenzene copolymers) in a dissolved (or highly swollen) state. In the case that the cross bridges are conformationally restricted, a spacious, rigid, open-structure network forms that provides the material with a complex of unusual properties,such as, the ability to swell in any kind of liquid, strongly adsorb all organic compounds both from aqueous and gaseous media. Manufactured by Purolite Int. (UK), the hypercrosslinked materials Macronet Hypersol MN have found large scale application as absorbents with unprecedented capacities, e.g., for waste water detoxification, sugar syrup decolonization, etc. 相似文献
90.
Putyato M. A. Valisheva N. A. Petrushkov M. O. Preobrazhenskii V. V. Chistokhin I. B. Semyagin B. R. Emel’yanov E. A. Vasev A. V. Skachkov A. F. Yurko G. I. Nesterenko I. I. 《Technical Physics》2019,64(7):1010-1016
Technical Physics - Problems arising in fabrication of lightweight flexible solar cells based on heteroepitaxial AIIIBV structures with substrate etching are discussed. Possible solutions are... 相似文献