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121.
A new formula is derived for the mass of spherically symmetric stellar configurations. An expression will be given where the mass square is connected to an integral over the pressure of gravitating matter. This formula turns out to hold for Newtonian gravity, for Einstein's GRT, for projective and bimetric scalar-tensor and further theories of gravitation. 相似文献
122.
From 1988 to 1989 radial velocities of 76 components of 46 Trapzium-type multiple systems have been measured with the 125-cm reflector of the Abastumani Astrophysical Observatory. In Table 1 a list of observations is given, containing the mean values of radial velocities, velocities of axial rotation, the halfwidth of contours and equivalent width. 相似文献
123.
虾壳红色素的抗氧化和抗肿瘤作用 总被引:8,自引:0,他引:8
为综合利用虾、蟹等水产品壳废料,采用有机溶剂萃取方法提取虾壳中的红色素,它是一类以虾青素及其酯为主的类胡萝卜素。比较虾壳红色素与维生素C在抑制小鼠肝匀浆脂质过氧化,以及抑制人大肠癌SW1116细胞株增殖的作用。结果表明虾壳红色素对小鼠肝匀浆脂质过氧化具有明显的抑制作用,其效果比维生素C强10倍以上;浓度为1×10-9及1×10-8mol/L虾壳红色素对人大肠癌SW1116细胞株增殖抑制率分别为23.4%和39.0%,在浓度为1×10-7mol/L中培养的细胞基本死亡。提示了虾、蟹壳废料潜在的应用价值。 相似文献
124.
Geomagnetism and Aeronomy - Photographic and video observations made by astronaut Thomas Pesquet (European Space Agency) during the 51st expedition to the International Space Station (ISS) contain... 相似文献
125.
The effect of abiotic and biotic factors on the properties of nano-size particles in freshwater bodies is considered. Field studies of the aquatic environments of Lake Ladoga ecosystem provided an experimental confirmation of the total water mineralization and organic matter content in the formation of nano-size particle properties under natural conditions. 相似文献
126.
In this paper, unusual optical phenomena observed in our country and abroad upon launches of Russian rockets are discussed and interpreted: they are regarded as the aftereffects of sunlight scattering by gas-dust clouds created by rocket fuel combustion products in different modes of engine operation. The results of instrumental observations of the clouds can be used to study physical processes in the upper atmosphere. 相似文献
127.
Various mechanisms of the formation of AlO molecules during the operation of solid-propellant rocket engines in the upper atmosphere and processes of AlO glow decay are considered. The main contribution to AlO formation at altitudes of 120–200 km is made by the interaction of metallic aluminum contained in products of solid propellant combustion with atmospheric oxygen. The decrease in the brightness of AlO clouds is caused by a decrease in the AlO concentration as a result of cloud expansion due to diffusion processes and AlO oxidation with atomic oxygen. 相似文献
128.
Izvestiya, Physics of the Solid Earth - In the research aimed at determining tectonic stresses from fault-slip data (the seismological data on the focal mechanisms of earthquakes, geological data... 相似文献
129.
A. M. Korzhenkov D. A. Moisieiev A. N. Ovsyuchenko A. S. Larkov A. V. Marahanov E. A. Rogozhin Sh. A. Emrullaev 《Seismic Instruments》2017,53(3):244-259
Archeological, archeoseismological, and seismotectonic studies were carried out in Salachik, the ancient capital of the Crimean Khans, on the outskirts of the modern city of Bakhchysarai, Crimea. The following damage and deformations of medieval buildings were observed: tilted building walls, shifted elements of building structures, rotation of fragments of walls and building blocks around the vertical axis, considerable deformations of arch structures, and fissures running through several rows of building blocks. These deformations are of a seismogenic nature. Traces of at least two strong ancient earthquakes were revealed in the medieval monuments of Salachik. Based on analysis of kinematic indicators, it is found that the maximum seismic intensity (VIII ≤ I 0 ≤ IX points) was due to an earthquake occurred in the west. Based on historical seismologic data, one of the two earthquakes is dated by April 30, 1698. Also, structural damage to buildings in Salachik was caused by Crimean earthquakes in 1927. The findings can be used for a comprehensive assessment of seismic hazards on the Crimean Peninsula. 相似文献
130.
Pozdynakov Sh. R. Briukhanov A. Yu. Kondrat’ev S. A. Ignat’eva N. V. Shmakova M. V. Minakova E. A. Rasulova A. M. Oblomkova N. S. Vasil’ev E. V. Terekhov A. V. 《Water Resources》2020,47(5):771-784
Water Resources - Estimate is made for the possible reduction of nutrient export from the drainage basins of tributaries of the Kuibyshev Reservoir through the introduction of the best available... 相似文献