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161.
Lithology and Mineral Resources - Upper Paleozoic sections in Taimyr comprise genetic rock complexes of different zones: deep-water shelf; offshore transition zone; shoals, deltas, and beaches of... 相似文献
162.
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
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REDUCE programs for algebraic computation in General Relativity are presented which use the metric tensor as input. The programs calculate — according to the user's option — the CHRISTOFFEL symbols, the RIEMANN tensor, the RICCI tensor, the RICCI scalar, the EINSTEIN tensor and the WEYL tensor. 相似文献
165.
K. M. Evans 《Geological Journal》1983,18(4):297-305
The Lynton Beds represent shallow marine sediments with a restricted fauna dominated by brachiopods. The age indicated by the brachiopod fauna is late Emsian, although the possibility of a younger date for the uppermost horizons cannot be discounted. 相似文献
166.
Numerical modelling of deep sea air-lift 总被引:2,自引:0,他引:2
Deep sea air-lifting of solid particles from depth of 1600 m is simulated with a mathematical model of the three-phase flow in an upward pipe. The computations are carried out for an axisymmetric domain in a transient way. Phase distributions, pressure and velocity profiles together with flow rates for all phases are presented and analysed. The influence of the pipe diameter on the air-lift efficiency was studied for air-lift pipes of different lengths and found to be significant. The lifting efficiency increases with the increase of the pipe diameter due to the reduction of the wall friction influence on the flow. In addition, the efficiency also increases with the increase of the solid particles volume fraction at the inlet. The presented numerical model can be utilized during various stages of the design of the air-lift pumps to help answer fundamental questions on the process, and during their operation to select optimal process parameters and to address possible problems. 相似文献
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A new version of the magnetic-tape catalog of ABELL clusters of galaxies is used to obtain redshift estimators and to generate two samples of clusters. A procedure for searching for superclusters of galaxies is applied and the results are given in tabular and graphic form. For a lmited homogeneous sample (distance 60–275 Mpc, galactic latitude B > 35°), 12 multiplets, having member clusters with known redshifts, are found. It is shown that the spatial covariance function for rich clusters has the form ξ = (r0/r)γ with r0 = 22.4 ± 1.8 Mpc and γ = 1.90 ± 0.25 for 3 Mpc ≲ r ≲ 80 Mpc. 相似文献