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21.
Deposits of the Lower Tauric suite (Upper Triassic) are exposed in the Kacha Anicline Uplift (Southeastern Crimea) near the source of the Bodrak River. Their rhythmostratigraphic, lithological, and paleontological charactristics are given for the first time; their tectonic position is determined and their age is specified. The principles for stratigraphic subdivision of the Tauric series are formulated.  相似文献   
22.
Absorption lines of some actinides, namely, actinium (Z = 89), protactinium (91), neptunium (93), plutonium (94), americium (95), curium (96), berkelium (97), californium (98), and einsteinium (99), were identified in the spectrum of one of the most peculiar main-sequence stars HD 101065 (Przybylski’s star). In the identification we used a high-resolution spectrum (R = 80 000) acquired at the 8.2-m ESO telescope.  相似文献   
23.
A complex approach is considered to the estimation of emissions of carbon gases formed during wildfires in the middle taiga subzone in the Yenisei region of Siberia. Based on the large-scale Siberian wildfires in 2012, the relative contribution of emissions to the values of background concentration of carbon gases (CO2, CH4, CO) in the atmospheric boundary layer measured at the 300-m ZOTTO tall tower is assessed. The degree of ecosystem damage caused by wildfires is estimated depending on their intensity and combustion phase (flame or flameless). Emission factors are calculated for the major carbon gases in wildfire plumes which are the key component for assessing wildfire emissions to the atmosphere.  相似文献   
24.
The daily parameters characterizing the field of surface air pressure from 1960 to 2014 are used for assessing the current trends in atmospheric circulation over the Azov–Black Sea region. It was revealed that the decrease in mean air pressure and the weakening of northeastern air trans port which was typical of the atmospheric circulation in this region in the previous period (1960–1990), occurred from 1991–1993 to 2005–2007. In recent 7–8 years, the ongoing air pressure drop is accom panied by the intensification of northeastern air transport.  相似文献   
25.
The kinetic-model (KM) efficiency in heavy-element nucleosynthesis calculations is analyzed. Various nucleosynthesis conditions and various mathematical models are considered. All basic two-particle reactions with neutrons, protons, α particles, and photons are taken into account. The results for the nuclear statistical equilibrium (NSE) model and for the KM are compared under various ambient conditions. The time it takes for the solution to become a steady-state one is estimated in the KM, provided that the NSE approximation holds. The computational processor time for temperatures T<8×109 K is shown to be modest, and the KM can be used for nucleosynthesis calculations in this range. The KM can be realized together with the NSE model at higher initial temperatures, with the results being smoothly joined by using the NSE solution as the initial KM approximation. The kinetic model can also be successfully used to compute the r-process under various physical conditions.  相似文献   
26.
Titanium is a rare, secondary nucleus among Galactic cosmic rays. Using the Silicon matrix in the ATIC experiment, Titanium has been separated. The energy dependence of the Ti to Fe flux ratio in the energy region from 5 GeV per nucleon to about 500 GeV per nucleon is presented. The article was translated by the authors.  相似文献   
27.
The concept of the r-process path is considered from the standpoint of a dynamic model. Rapid nucleosynthesis is shown to proceed not along certain preferential lines called the r-process paths but in the region of nuclei bounded on the one side by the existing nuclei and on the other side by nuclei upon reaching which the r-process enters a cooling phase. This view is shown to account for the main heavy-element abundance patterns.  相似文献   
28.
The most recent fission-barrier calculations based on improved mass formulas indicate that the adopted values are underestimated. We analyze the dependence of the fission rates on the fission barrier and show that an increase in the fission barriers leads not so much to a decrease in the importance of fission as to the possible synthesis of heavier elements in the r-process. The rates of induced fission of most isotopes with Z>80 at astrophysical energies have been calculated for the first time for fission barriers obtained from different theoretical models.  相似文献   
29.
Panov  I. V.  Yudin  A. V. 《Astronomy Letters》2020,46(8):518-527
Astronomy Letters - The nucleosynthesis of heavy elements in the scenario for the evolution of a close binary of neutron stars differing greatly in mass is considered. In contrast to the scenario...  相似文献   
30.
Photometric observations of the Ap star HD 193722 give unambiguous proofs for a rotational period of P=8.5297 days in contradiction to the earlier found value of P=1.13316 days. Spectroscopic measurements yield a line width equivalent to the value v sin i=44.5 km/s. Both findings show convincingly that HD 193722 is an evolved Ap star with a position in the giant region of the HR diagram. This place falls into a domain occupied by the hypothetic Maia sequence.  相似文献   
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