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1.
Israel Gohberg Naum Krupnik Ilya Spitkovsky 《Integral Equations and Operator Theory》1993,17(3):322-337
The Banach algebra generated by one-dimensional linear singular integral operators with matrix valued piecewise continuous coefficients in the spaceL
p
(,) with an arbitrary weight is studied. The contour consists of a finite number of closed curves and open arcs with satisfy the Carleson condition. The contour may have a finite number of points of selfintersection. The symbol calculus in this algebra is the main result of the paper. 相似文献
2.
Andrey Galukhin Ilya Nikolaev Roman Nosov Sergey Vyazovkin 《Molecules (Basel, Switzerland)》2022,27(11)
This study highlights the value of nonisothermal kinetic methods in selecting temperature conditions for the isothermal preparation of microporous polymeric materials. A dicyanate ester is synthesized and the kinetics of its polymerization in diphenyl sulfone are studied by calorimetry under nonisothermal conditions. The kinetics are analyzed by a model-based approach, using the Kamal model, as well as by a model-free approach, using an advanced isoconversional method. Both approaches correctly predict the time to completion of polymerization at a given temperature. The material prepared independently at the predicted temperature is characterized by electron microscopy and CO2 adsorption measurements and is confirmed to possess a microporous structure with a multimodal distribution of micropores with two major maxima at ~0.5 and 0.8 nm. 相似文献
3.
Chi-Kwong Li Ilya M. Spitkovsky 《Journal of Mathematical Analysis and Applications》2003,282(1):329-340
Existence of the fractional powers is established in Banach algebra setting, in terms of the numerical ranges of elements involved. The behavior of the spectra and (for Hermitian ∗-algebras satisfying some additional hypotheses) the ∗-numerical range under taking these powers also is investigated. 相似文献
4.
Measurable spectra are often derived from contractions of many-body Green's functions. One calculates hence more information than needed. Here we present and illustrate an in principle exact approach to construct effective potentials and kernels for the direct calculation of electronic spectra. In particular, a dynamical but local and real potential yields the spectral function needed to describe photoemission. We discuss for model solids the frequency dependence of this "photoemission potential" stemming from the nonlocality of the corresponding self-energy. 相似文献
5.
A system of two coupled oscillators, each of them coupled to an independent reservoir, is analysed. The analytical solution of the non-rotating wave master equation is obtained in the high-temperature and weak coupling limits. No thermal entanglement is found in the high-temperature limit. In the weak coupling limit the system converges to an entangled non-equilibrium steady state. A critical temperature for the appearance of quantum correlations is found. 相似文献
6.
Veselov Mark S. Ivanenkov Yan A. Yamidanov Renat S. Osterman Ilya A. Sergiev Petr V. Aladinskiy Vladimir A. Aladinskaya Anastasia V. Terentiev Victor A. Ayginin Andrey A. Skvortsov Dmitry A. Komarova Katerina S. Chemeris Alexey V. Baimiev Alexey Kh. Sofronova Alina A. Machulkin Alexey E. Petrov Rostislav A. Maklakova Svetlana Yu. Bezrukov Dmitry S. Filkov Gleb I. Zainullina Liana F. Maximova Marina A. Zileeva Zulfiya R. Kartsev Victor G. Vakhitova Yulia V. Dontsova Olga A. 《Molecular diversity》2020,24(1):233-239
Molecular Diversity - A series of 5-oxo-4H-pyrrolo[3,2-b]pyridine derivatives was identified as novel class of highly potent antibacterial agents during an extensive large-scale high-throughput... 相似文献
7.
8.
Vorobeichik I Narevicius E Rosenblum G Orenstein M Moiseyev N 《Physical review letters》2003,90(17):176806
We report on tunneling enhancement in a periodically perturbed double well system. The double well system was realized by a structure of two optical waveguides. The transfer of light power from one waveguide to the another as induced by the periodic variations of the waveguide geometry was investigated. Our experimental measurements show that, in the presence of periodic perturbation, this transfer of light power can be enhanced by more than 500 times. We use an analogy between electromagnetic wave optics and the quantum wave phenomena to provide an experimental support to the theoretical model of tunneling enhancement of a quantum particle, facilitated by its interaction with auxiliary quantum states. 相似文献
9.
The variation of the structure of the control parameter space for a nonautonomous nonlinear oscillator is demonstrated with a harmonically excited nonautonomous oscillatory circuit with a piecewise linear capacitance. 相似文献
10.
Udovydchenkov IA Brown MG Duda TF Mercer JA Andrew RK Worcester PF Dzieciuch MA Howe BM Colosi JA 《The Journal of the Acoustical Society of America》2012,131(6):4409-4427
The results of mode-processing measurements of broadband acoustic wavefields made in the fall of 2004 as part of the Long-Range Ocean Acoustic Propagation Experiment (LOAPEX) in the eastern North Pacific Ocean are reported here. Transient wavefields in the 50-90 Hz band that were recorded on a 1400-m long 40 element vertical array centered near the sound channel axis are analyzed. This array was designed to resolve low-order modes. The wavefields were excited by a ship-suspended source at seven ranges, between approximately 50 and 3200 km, from the receiving array. The range evolution of broadband modal arrival patterns corresponding to fixed mode numbers ("modal group arrivals") is analyzed with an emphasis on the second (variance) and third (skewness) moments. A theory of modal group time spreads is described, emphasizing complexities associated with energy scattering among low-order modes. The temporal structure of measured modal group arrivals is compared to theoretical predictions and numerical simulations. Theory, simulations, and observations generally agree. In cases where disagreement is observed, the reasons for the disagreement are discussed in terms of the underlying physical processes and data limitations. 相似文献