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421.
It is shown that the annealing kinetics of fission tracks in apatite can be described by a sum of exponential decay functions. From an analysis of the temperature dependence of this annealing law it is concluded that the etchability of fission tracks is due to extended defects, i.e. systems of dislocation loops. The multiexponential annealing law is also applied to prove that the plateau correction method is basically correct, but rather as a method for determining a lower limit than the “true” fission track age. 相似文献
422.
Geotectonics - Synthesis of the results of U–Pb dating of detrital zircons (dZr) from the Uppermost Precambrian–Phanerozoic strata of the southern and southeastern framing of the East... 相似文献
423.
R. R. Gabdullin N. V. Badulina E. A. Bakai E. V. Rubtsova A. Yu. Yurchenko E. V. Karpova A. V. Ivanov M. A. Varzanova A. V. Sergienko T. A. Konovalova M. V. Parakhina 《Moscow University Geology Bulletin》2018,73(4):346-360
The composition and origin of the Callovian–Oxfordian deposits of the Sudak Bay were characterized on the basis of the generalization and analysis of our own results, as well as published and unpublished data. The botanical future was first implemented for the geological mapping of the Oxfordian deposits. 相似文献
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The accuracy of differential scanning calorimetry (DSC) on a heat capacity measurement was evaluated using MgO. The result indicated that the deviation of the result in comparison to literature values was less than 0.4% at temperatures above 300 K and 2.1% below this temperature. Since this experiment proved the reliability of DSC, heat capacity, compressibility, and thermal expansion of ilmenite-type MgGeO3 were measured by means of DSC, a diamond anvil high pressure device, and a high-temperature X-ray camera, respectively. The heat capacity was approximated by C p = a + b·T + c·T ?2 at high temperatures and by the Debye function at low temperatures. The compressibility was well-represented by the Murnaghan-Birch equation of 2nd order. The thermal expansion coefficient was constant up to 1073 K. 相似文献
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Zagidullin A. A. Usanin V. S. Petrova N. K. Nefedyev Yu. A. Andreev A. O. Gudkova T. V. 《Astronomy Reports》2020,64(12):1093-1106
Astronomy Reports - The work is devoted to the study of the physical libration of the Moon. Interest in the traditional topic related to the rotation of the Moon is stirred up by the activity of... 相似文献
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A 90 s time resolution study of the soft X-ray emission from three active region loops shows the emission to be constant to about two percent over the half hour period of observation. Soft X-ray observations in two wavebands are used to deduce the temperature and density of these loops. The data unambiguously demonstrate that energy is supplied to each loop during the observations. If heating is due to discrete events, the time interval between events is shown to be less than 10 min, which is short relative to the radiative cooling time of the loops.Skylab Solar Workshop Post-Doctoral Appointee, 1975–1977. The Skylab Solar Workshops are sponsored by NASA and NSF and managed by the High Altitude Observatory, National Center for Atmospheric Research. 相似文献