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901.
902.
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
903.
904.
905.
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
906.
Dolgikh G. I. Dolgikh S. G. Vasilevskaya L. N. Lisina I. A. 《Doklady Earth Sciences》2020,490(1):18-22
Doklady Earth Sciences - The interaction between the atmosphere and the lithosphere in the minute range of periods is considered. The technique of assessment of the influence of atmospheric... 相似文献
907.
Doklady Earth Sciences - Based on the results of studying the lithological–geochemical features of the Upper Jurassic–Lower Cretaceous mudrocks and black shales in the Eastern Russian... 相似文献
908.
M.A. Janssen R.D. Lorenz F. Paganelli R.L. Kirk S.D. Wall Y. Anderson P. Callahan G.A. Hamilton L. Roth A. Le Gall the Cassini Radar Team 《Icarus》2009,200(1):222-239
The first comprehensive calibration and mapping of the thermal microwave emission from Titan's surface is reported based on radiometric data obtained at 2.2-cm wavelength by the passive radiometer included in the Cassini Radar instrument. The data reported were accumulated from 69 separate observational segments in Titan passes from Ta (October 2004) through T30 (May 2007) and include emission from 94% of Titan's surface. They are diverse in the key observing parameters of emission angle, polarization, and spatial resolution, and their reduction into calibrated global mosaic maps involved several steps. Analysis of the polarimetry obtained at low to moderate resolution (50+ km) enabled integration of the radiometry into a single mosaic of the equivalent brightness temperature at normal incidence with a relative precision of about 1 K. The Huygens probe measurement of Titan's surface temperature and radiometry obtained on Titan's dune fields allowed us to infer an absolute calibration estimated to be accurate to a level approaching 1 K. The results provide evidence for a surface that is complex and varied on large scales. The radiometry primarily constrains physical properties of the surface, where we see strong evidence for subsurface (volume) scattering as a dominant mechanism that determines the emissivity, with the possibility of a fluffy or graded-density surface layer in many regions. The results are consistent with, but not necessarily definitive of a surface composition resulting from the slow deposition and processing of organic compounds from the atmosphere. 相似文献
909.
Hemant K. Badola Jitendra S. Butola 《山地科学学报》2005,2(2):173-180
This paper examines the effect of ploughing depths (A -- 60 cm, B -- 45 cm and C -- 30 cm) on the growth and yield of Heracleum candicans Wall (Apiaceae), a threatened medicinal herb of the Himalayan region. This less-explored plant is being suggested as a potential crop for the mountain agriculture. The study was carried out in an orchard in Himachal Pradesh, India at 2500 m altitude, for two successive growth years. During the first year, all plants remained in juvenile state; in the second year, nearly 65 % plants produced flowers only under 60cm ploughing depth. Among its morphological traits, plant height, collar diameter and aboveground flesh weight were found to be strongly correlated (P 〈 0.01) with the belowground biomass during the first year (r =0.968, 0.925 and 0.973, respectively) and during the second year (r=0.945, 0.928 and 0.775, respectively). Increase in the ploughing depth was significantly correlated (P〈0.01) with all growth parameters, including the belowground dry weight, marketable portion of the produce. The belowground biomass (commercial yield; 16.28 Qt/hec) at depth A was about 2.6 and 4.7 times higher than those recorded at depths B and C, respectively. The results clearly justify the importance of deep ploughing and this paper strongly recommends it for economically sustainable cropping. 相似文献
910.
We solve a plane problem of linear baroclinic seiches in closed rotating basins of variable depth with two-layer density stratification.
In the long-wave approximation, we get a boundary-value problem for a system of ordinary differential equations and propose
a numerical procedure for finding internal seiches. The analytic solutions of the problem are obtained for a basin of constant
depth. The numerical analysis of seiches is performed for the distributions of depth corresponding to the zonal and meridional
sections of the Black Sea and model basins including the cases of a shelf zone and an underwater ridge. It is shown that the
baroclinic seiches become more intense in shallow-water regions and that the intense longshore currents caused by Earth’s
rotation are formed in the shelf zones and over the underwater ridges. 相似文献