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31.
O. V. Zolotov B. E. Prokhorov A. A. Namgaladze O. V. Martynenko 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(3):435-438
The morphological features in the deviations of the total electron content (TEC) of the ionosphere from the background undisturbed
state as possible precursors of the earthquake of January 12, 2010 (21:53 UT (16:53 LT), 18.46° N, 72.5° W, 7.0 M) in Haiti
are analyzed. To identify these features, global and regional differential TEC maps based on global 2-h TEC maps provided
by NASA in the IONEX format were plotted. For the considered earthquake, long-lived disturbances, presumably of seismic origin,
were localized in the near-epicenter area and were accompanied by similar effects in the magnetoconjugate region. Both decreases
and increases in the local TEC over the period from 22 UT of January 10 to 08 UT of January 12, 2010 were observed. The horizontal
dimensions of the anomalies were ∼40° in longitude and ∼20° in latitude, with the magnitude of TEC disturbances reaching ∼40%
relative to the background near the epicenter and more than 50% in the magnetoconjugate area. No significant geomagnetic disturbances
within January 1–12, 2010 were observed, i.e., the detected TEC anomalies were manifestations of interplay between processes
in the lithosphere-atmosphere-ionosphere system. 相似文献
32.
A.D. ProkhorovA.A. Prokhorov L.F. ChernyshV.P. Dyakonov H. Szymczak 《Journal of magnetism and magnetic materials》2011,323(11):1546-1550
The ground state of Gd3+ ions substituting for trivalent europium in the EuAl3(BO3)4 single crystal was studied by electron paramagnetic resonance (EPR) over the temperature range of 300-4.2 K and at pressures up to 9 kbar. The EPR spectra were analysed using the spin Hamiltonian of axial symmetry. The following parameters are reported: g=1.981±0.002, b20=280.18±0.12, b40=−12.95±0.08 and b60=0.61±0.12 (at Т=298 K). The distortions of the nearest environment of Gd3+ ion were analysed within the framework of the superposition model of crystal field. 相似文献
33.
34.
L. Baratchart V. A. Prokhorov E. B. Saff 《Foundations of Computational Mathematics》2001,1(4):385-416
Let E \subset(-1,1) be a compact set, let μ be a positive Borel measure with support \supp μ =E , and let H
p
(G),
1≤ p ≤∈fty, be the Hardy space of analytic functions on the open unit disk G with circumference Γ={z \colon |z|=1} . Let Δ
n,p
be the error in best approximation of the Markov function \frac{1}{2π i} ∈t_E \frac{d μ(x)}{z-x} in the space L
p
(Γ) by meromorphic functions that can be represented in the form h=P/Q , where P ∈ H
p
(G),
Q is a polynomial of degree at most n , Q\not \equiv 0 . We investigate the rate of decrease of Δ
n,p
,
1≤ p ≤∈fty , and its connection with n -widths. The convergence of the best meromorphic approximants and the limiting distribution of poles of the best approximants
are described in the case when 1<p≤∈fty and the measure μ with support E=[a,b] satisfies the Szegő condition ∈t_a^b \frac{\log(d μ/ d x)}{\sqrt{(x-a)(b-x)}} dx >- ∈fty.
July 27, 2000. Final version received: May 19, 2001. 相似文献
35.
Atomic force microscopy (AFM) has been applied to visualize expanded linear chain and compact crystalline conformations of ultrahigh molecular weight polyethylene (PE) molecules deposited on mica and graphite from diluted solutions at elevated temperatures. Isolated PE chains are visualized on mica with the apparent negative AFM height and the contour length much shorter than the molecular length. The chain conformations have both the kinked random‐coil sites and the sites of the unexpectedly large two‐dimensional expansion. The crystalline conformations on mica are small single‐molecule rod‐like nanocrystallites and the isolated block‐type “edge‐on” nanolamellae comprising several PE molecules. Noticeable fluctuations of the fold length in the range of approximately 10–20 nm around the averaged value of about 15 nm are observed for nanocrystallites and on tips of some nanolamellae. The explanation of the experimentally observed features of chain surface conformations on mica is proposed. It implies the immobilization of PE molecules in the nm‐thickness salt layer formed on mica surface at ambient conditions after PE deposition and the presence along the chain of multiple expanded chain folds. Only isolated lamellae and lamellar domains of a monolayer height are observed on graphite samples. The substrate/polymer epitaxial incommensurability important for the observation of the PE linear chain surface conformations is discussed from the comparison of the results obtained for mica and graphite, the coil‐to‐crystal intramolecular transformation is assumed to be inhibited on mica surface. The slow disintegration of the original gel structure of PE stock‐solution used for the high‐temperature depositions was found to result in the characteristic large‐scale morphological heterogeneity of the samples. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 766–777, 2010 相似文献
36.
The theoretical investigation of the hyper-Raman scattering by 2LO phonons is carried when the doubled energy of incident photons lies near the band gap of a semiconductor. The scattering process is considered, taking into account the Wannier excitons as intermediate states. 相似文献
37.
A. S. Prokhorov V. B. Anzin D. A. Vitukhnovskiĭ E. S. Zhukova I. E. Spektor B. P. Gorshunov S. Vongtragool M. B. S. Hesselberth J. Aarts G. J. Nieuwenhuys M. Dumm D. Faltermeier S. Kaiser S. Yasin M. Dressel N. Drichko 《Journal of Experimental and Theoretical Physics》2006,103(6):887-896
The electrodynamic response of spin glasses (in the form of thin AuFe films) in the terahertz frequency range has been studied using backward-wave oscillator (BWO) spectroscopy (10–40 cm?1) and optical ellipsometry (5000–33000 cm?1) techniques at temperatures from 5 to 295 K. The room-temperature dynamic conductivity spectra of AuFe films are typical of metals and can be described within the framework of the Drude theory of conduction by free charge carriers. Changes in the microscopic parameters of charge carriers in AuFe films with increasing iron content, which are related to additional scattering of carriers on the impurity magnetic moments, have been studied on the quantitative level, including the carrier relaxation frequency and characteristic time, plasma frequency, and conductivity. It is established that the spin-glass phase at a temperature of ~5 K exhibits dispersion of the conductivity in the frequency range 10–40 cm?1, which can be related to the appearance of a mobility gap in the subsystem of free electrons involved in the RKKY interaction between magnetic centers (Fe atoms). 相似文献
38.
The shadow flow pattern behind a horizontal cylinder uniformly towed in a stratified fluid with constant buoyancy frequency
(in the imbedded vortex and turbulent wake regime) is recorded synchronously with acoustic echo sounding (basic frequency
equal to 1 MHz) in a laboratory tank. Using computer processing, the illumination profiles in the schlieren pattern are constructed
on scales comparable with the sounding acoustic ray width. Although the optical and acoustic profiles are not similar, nevertheless
they enable the basic structural elements of the wake, including its high-gradient core to be identified, and their time variability
traced. The features of the integral acoustic scattering characteristic, in particular, the volume scattering strength, allow
this characteristic to be used, together with optical images of the flow pattern, to distinguish the flow regime identification
criteria.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 5–17, May–June, 1998.
The work was partly financed by the Russian Foundation for Basic Research (projects Nos. 96-05-64004 and 97-01-01013) and
by INTAS Grant No. 93-1584. 相似文献
39.
M. A. Kazaryan Yu. M. Mokrushin A. M. Prokhorov O. V. Shakin 《Journal of Russian Laser Research》1997,18(6):507-514
The possibility of using metal-vapor lasers and picture brightness enhancers for improving the sharpness of TV picture projection on a large screen is demonstrated. 相似文献
40.
Zh. I. Alferov A. F. Andreev A. S. Borovik-Romanov A. A. Boyarchuk V. L. Ginzburg S. N. Zhurkov L. V. Keldysh A. V. Kurdyumov I. P. Kushnir N. P. Lyakishev B. M. Mogutnov V. V. Nemoshkalenko Yu. A. Osip’yan B. E. Paton E. G. Ponyatovskii A. M. Prokhorov I. A. Tomilin V. I. Trefilov V. Sh. Shekhtman 《Physics of the Solid State》1997,39(6):1016-1018