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991.
Doklady Earth Sciences - The first results of studies of vertical particle fluxes in a hydrothermal sedimentary system of a subpolar area of the Mid-Atlantic Ridge under the influence of... 相似文献
992.
Mathematical Geosciences - Manually interpreting multivariate drill hole data is very time-consuming, and different geologists will produce different results due to the subjective nature of... 相似文献
993.
Tension-Only Concentrically Braced Frames (TOCBF) exhibit deteriorating pinched hysteretic behaviour during strong earthquakes. Slender braces transit between an elastic buckling state, a restraightening state, in which they carry almost no load, an elastic tensile loading state as they are suddenly taut and, finally, a tensile yielding state. It has long been suspected that the sudden increase in tensile forces in the braces of TOCBSF creates detrimental impact loading on the connections and other structural elements. No experimental evidence, however, has been provided so far to confirm, or to quantify, this impact phenomenon. This paper addresses this issue through shake table tests of half scale, two-storey, TOCBF models. By normalizing the hysteresis loops of braces obtained from shake table tests to the yield strength of steel obtained from quasi-static tests, the increase in tensile forces in the braces was obtained. Results of dynamic tensile tests on steel coupons under similar strain rates as observed during the shake table tests showed that this increase in tensile forces is not the result of impact, but is rather caused by a yield strength increase of the steel under high strain rate. A procedure is proposed to estimate and account for this increase in tensile forces in the braces at the design stage. 相似文献
994.
Solar System Research - Within the framework of Tsallis nonextensive statistics, the criteria for the Jeans gravitational instability are derived for a self-gravitating protoplanetary disk, whose... 相似文献
995.
Cheptsov V. S. Belov A. A. Vorobyova E. A. Pavlov A. K. Tsurkov D. A. Frolov D. A. Lomasov V. N. Chumikov A. E. 《Solar System Research》2021,55(5):383-388
Solar System Research - Ionizing radiation is one of the main factors that destroy biomolecules in extraterrestrial conditions. The effects of radiation depend on the conditions of the exposure... 相似文献
996.
Slyuta E. N. Marov M. Ya. Dunchenko A. G. Makovchuk V. Yu. Morozov O. V. Nazarov A. I. Ivanov V. V. Pogonin V. I. Roskina E. G. Safronov V. V. Kharlov B. N. Tatsiy L. P. 《Solar System Research》2021,55(5):446-466
Solar System Research - The device is being developed for the TERMO-LR experiment on the Luna-27 lunar lander; it is intended for contact geophysical measurements of various properties of the lunar... 相似文献
997.
Solar System Research - A numerical-analytical method for analyzing the orbital evolution of a planetary satellite under the influence of a perturbing body moving in an elliptical orbit is... 相似文献
998.
Astrophysics - A general catalog of active galactic nuclei (AGN) has been created from identified optical sources of X-ray data from the Hamburg-ROSAT Catalog (HRC) and the Byurakan-Hamburg ROSAT... 相似文献
999.
Astronomy Letters - Techniques for solving the problem of constructing a Stäckel model by generalizing the potential from the equatorial plane to the entire space are considered. The initial... 相似文献
1000.
Astronomy Letters - The primordial $${}^{4}$$ He abundance (Y $${}_{p}$$ ) is one of the key characteristics of Primordial Nucleosynthesis processes that occurred in the first minutes after the Big... 相似文献