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101.
Sergii I. Shylin Vadim Ksenofontov Sergey A. Medvedev Claudia Felser 《Journal of Superconductivity and Novel Magnetism》2016,29(3):573-576
Although pairing mechanism in unconventional superconductors is still an open question, the density of states at the Fermi level is considered to be one of the factors affecting the superconducting transition temperature. Herein, we report on 57Fe-Mössbauer studies of β-FeSe, FeSe 0.5Te 0.5, and Rb 0.8Fe 1.6Se 2 superconductors as well as two intercalate products consisting of FeSe layers and a lithium-containing molecular spacer in between. In these materials, the hyperfine parameters of 57Fe are directly related to the 3d-electron density on Fe atoms and show strong correlation with superconducting properties. 相似文献
102.
Sergey Valery Samoilenko 《Information Technology for Development》2013,19(1):40-61
One of the routes by which investments in information and communication technologies (ICT) could impact a macroeconomic bottom line of economies is by contributing to total factor productivity (TFP), an important component of economic growth. While the more traditional “investments to revenues” resource-intensive path has been well researched, the nature of the indirect “investments to TFP” link remains much less clear. Specifically, it is not well understood what conditions must be present for economies to exhibit the relationship between investments and TFP. In the current study, conducted in the context of 18 transition economies in Europe and the former Soviet Union, we aim to identify some of the factors associated with the presence of the relationship between the subset of investments in ICT, investments in telecoms, and two components of TFP – change in efficiency and change in technology. The results of the analysis of the data set spanning from 1993 to 2002 suggest that while the presence of the link between investments and change in technology was associated with the level of investments, the presence of the relationship between investments and change in efficiency was associated with the quality of a full-time telecom workforce. The consequent analysis of the data set spanning from 2003 to 2008 supports this finding and also provides evidence of the importance of the macroeconomic strategies that balance an increase in the levels of investments with the increase in the levels of efficiency of utilization of investments and the generation of revenues. 相似文献
103.
Sergey Edward Lyshevski 《International journal of systems science》2013,44(15):2770-2780
This paper formulates and solves control problems for nonlinear microsystems which comprise micro-electromechanical devices, micromachined transducers and microelectronics. We perform a consistent dynamic analysis and coherent designs with a minimum level of simplifications using high-fidelity mathematical models. The proposed methodology enables practical implementation for multi-input/multi-output systems due to overall conceptual consistency, design coherence, computational efficiency, algorithmic effectiveness and hardware simplicity. Various issues in nonlinear analysis and control are examined and experimentally verified substantiating design concepts for high-performance microsystems. The reported findings are demonstrated for a proof-of-concept closed-loop electrostatic microactuator. 相似文献
104.
Oleg Bazhenov Vladimir Burlakov Sergey Dolgii Aleksey Nevzorov Natalya Salnikova 《International journal of remote sensing》2013,34(11):3024-3032
We consider the results of long-term remote optical monitoring obtained at the Siberian Lidar Station of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk (56° 30′ N, 85° E). The scattering characteristics of stratospheric aerosol layer, obtained according to data of lidar measurements recorded since 1986, are presented. We analyse the trends of changes in the total ozone (TO) content over Tomsk for the period 1996–2013 according to data of spectrophotometric measurements employing Total Ozone Mapping Spectrometer (TOMS) data for the period 1979–1994. We determined the periods of elevated content of stratospheric aerosol over Tomsk after a series of explosive eruptions of volcanoes in the Pacific Ring of Fire and Iceland in 2006–2011. Since the second half of the 1990s we have recorded an increasing TO trend, equalling 0.65 DU/year for the period 1996–2013. 相似文献
105.
Remote-sensing approaches for environmental protection and exploration have evolved rapidly in the last decade. Among the new operational tools, hyperspectral Fluorescent LiDAR System (FLS®) lidar has demonstrated a high sensitivity and the ability to function in complex environments for real-time, robust oil-spill monitoring on airborne or ship-borne analytical platforms. The capabilities of such analytical platforms include real-time analysis of laser-induced fluorescence (LIF) data. Although numerous examples of the application of signal theory to the analysis of hyperspectral data appear in the remote-sensing literature, the conventional data analysis strategies are not well adapted to the practical issues of the LIF applications. The aim of this article is to provide a new approach for LIF lidar analytical platforms, which is focused on the specifics of hyperspectral LIF data. The approach is based on structural data analysis and interpretation, through which more detailed spectral matching is performed. This article is based on a simulated experiment in which the spectra of actual seawater and well-known types of petroleum products were combined to demonstrate the wavelet-transform-based analysis of LIF data. The final part of the article demonstrates the application of the wavelet transform to the structural analysis of LIF data from field experiments for the detection and identification of oil products in difficult environmental conditions. 相似文献
106.
Oleg N. Grigoriev Boris A. Galanov Vladimir A. Lavrenko Alla D. Panasyuk Sergey M. Ivanov Alexandr V. Koroteev Klaus G. Nickel 《Journal of the European Ceramic Society》2010,30(11):2397-2405
The oxidation of ZrB2–SiC and ZrB2–SiC–ZrSi2 ceramics of different composition has been studied experimentally at 1500 °C in pure oxygen for up to 50 h. ZrB2–SiC–ZrSi2 ceramics proved to be the most oxidation-resistant at ZrSi2 contents of less then 4 wt%. These ceramics were more oxidation-resistant than ZrB2–SiC ceramics. An analytical model of growth kinetics for a multilayered scale based on an oxidation–diffusion balance was developed and tested. 相似文献
107.
Mikhail B. Novikov Tatiana A. Borodulina Sergey V. Kotomin Valery G. Kulichikhin 《The Journal of Adhesion》2013,89(1):77-107
Relaxation properties of pressure-sensitive adhesives (PSA) have been studied with the squeeze-recoil tester used in the regime of parallel-plate dilatometer under conditions imitating the removal of compressive force in the course of adhesive bond formation. The relaxation properties of PSAs are compared with their adhesive behavior measured using the 180-Deg Peel Test. Two classes of PSAs are considered: 1) conventional rubbery adhesives based on the mixtures of styrene-isoprene-styrene (SIS) block copolymer with a tackifier resin and a plasticizer, and butyl rubber plasticized with low-molecular-weight polyisobutylene, and 2) hydrophilic PSAs composed of the blends of high-molecular-weight poly(N-vinyl pyrrolidone) (PVP) with oligomeric polyethylene glycol (PEG). By comparing the adhesive and relaxation behaviors of different PSAs, the relaxation criteria for pressure-sensitive adhesion have been stated. Relaxation behavior of the examined PSAs demonstrates two values of retardation time: the shorter retardation time of 10–70?sec and the longer time of 300–660?sec. These times can be associated, respectively, with small- and large-scale mechanisms of strain recovery. By comparing the relaxation and adhesive properties of PVP-PEG blend (which involves the formation of a hydrogen-bonded network through both terminal hydroxyl groups in PEG short chains) with the properties of covalently crosslinked copolymers of vinyl pyrrolidone (VP) with PEG-diacrylate and comb-like VP copolymers with PEG-monomethacrylate, the contributions of covalent crosslinking and H-bonding network have been characterized. 相似文献
108.
Sergey V. Kuzikov Mikhail E. Plotkin Nikolay I. Zaitsev 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(2):121-131
An output mode converter for Ka-band multi-MW gyroklystron in the Institute of Applied Physics (IAP) operating in the TE53 mode is suggested. Two variants of the converter, aimed for different applications, are presented: the TE53 to TE01 mode converter with power output along the device axis and the TE53 mode to Gaussian wavebeam quasi-optical converter with a visor. The suggested designs include the built-in electron beam
collector. The converters were designed using a new synthesis algorithm, which implies iterative improvement of the waveguide
wall shape in order to achieve high efficiency. The calculation results were proven by HFSS simulation and low-power tests
of one version of the converter. 相似文献
109.
110.
Günter Mistlberger Klaus Koren Elisabeth Scheucher Daniel Aigner Sergey M. Borisov Armin Zankel Peter Pölt Ingo Klimant 《Advanced functional materials》2010,20(11):1842-1851
Magnetic optical sensor particles with multifunctional cores and shells are synthesized via a facile nanoprecipitation method and the subsequent modification of the particle shell. The hydrophobic particle core includes optical oxygen indicators, a light harvesting system, photosensitizers, and magnetic nanoparticles. Further functionalities are introduced by modifying the shell with enzymes, antibodies, multiple layers of polyelectrolytes, stimuli‐responsive polymers, and luminescent indicator dyes. The hydrodynamic diameter is tunable by varying different precipitation parameters. 相似文献