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31.
Maria Aldona Augustyniak-Jabłokow Yurii V. Yablokov Bartłomiej Andrzejewski Wojciech Kempiński Szymon Łoś Krzysztof Tadyszak Mikhail Y. Yablokov Valentin A. Zhikharev 《Physics and Chemistry of Minerals》2010,37(4):237-247
The X-band EPR and magnetic susceptibility in the temperature range 4.2–300 K study of the shungite-I, natural nanostructured
material from the deposit of Shunga are reported. Obtained results allow us to assign the EPR signal to conduction electrons,
estimate their number, N
P, and evaluate the Pauli paramagnetism contribution to shungite susceptibility. A small occupation (~5%) of the localized
nonbonding π states in the zigzag edges of the open-ended graphene-like layers and/or on σ (sp
2+x
) orbitals in the curved parts of the shungite globules has been also revealed. The observed temperature dependence of the
EPR linewidth can be explained by the earlier considered interaction of conduction π electrons with local phonon modes associated
with the vibration of peripheral carbon atoms of the open zigzag-type edges and with peripheral carbon atoms cross-linking
different nanostructures. The relaxation time T
2 and diffusion time T
D are found to have comparable values (2.84 × 10−8 and 1.73 × 10−8 s at 5.2 K, respectively), and similar dependence on temperature. The magnetic measurements have revealed the suppression
of orbital diamagnetism due to small amount of large enough fragments of the graphene layers. 相似文献
32.
S. Gburek J. Sylwester M. Kowalinski J. Bakala Z. Kordylewski P. Podgorski S. Plocieniak M. Siarkowski B. Sylwester W. Trzebinski S. V. Kuzin A. A. Pertsov Yu. D. Kotov F. Farnik F. Reale K. J. H. Phillips 《Solar System Research》2011,45(3):189-199
The goals and construction details of a new design Polish-led X-ray spectrophotometer are described. The instrument is aimed to observe emission from entire solar corona and is placed as a separate block within the Russian TESIS X- and EUV complex aboard the CORONAS-PHOTON solar orbiting observatory. SphinX uses silicon PIN diode detectors for high time resolution measurements of the solar spectra in the range 0.8–15 keV. Its spectral resolution allows for discerning more than hundred separate energy bands in this range. The instrument dynamic range extends two orders of magnitude below and above these representative for GOES. The relative and absolute accuracy of spectral measurements is expected to be better than few percent, as follows from extensive ground laboratory calibrations. 相似文献
33.
Much has been said, yet little remains known, about the impacts of the changes associated with post-socialist transition on housing inequalities in metropolitan Central and Eastern Europe. To some extent, this depends on the scarcity of ‘hard evidence’ about the socialist epoch against which the subsequent developments may be gauged. Based on a case study of Bucharest, the Romanian capital and one of the region’s major cities, this study investigates various lines of housing inequality using data from a 20 % sample of the national censuses of 1992 and 2002. With only minor changes having taken place since the revolutionary events of late 1989, the year 1992 provides an accurate picture of the housing inequalities inherited from the socialist epoch, whereas the new societal order had largely been established by 2002. We use linear regression and binary logistic regression modeling to identify the factors that predict living space and level of facilities. The results suggest that the first decade of transition did not exert any major influences on the housing inequalities inherited from socialism, with the exception of notable improvements at the very top of the social pyramid. This finding is at odds with the literature that highlights the (suggested) effects of socio-economic polarization on the residential structure of cities after socialism. However, the results from 1992 indicate that housing was segmented along socio-economic lines already under socialism, and perhaps more so than one would have expected in the light of the literature on housing inequalities during this period. 相似文献