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101.
R. F. Griffin 《Journal of Astrophysics and Astronomy》1982,3(4):383-392
Photoelectric radial-velocity measurements have confirmed O. C. Wilson’s finding that BD 33° 2206, the secondary star in the
wide visual binary ADS 8470, is a spectroscopic binary. It has an eccentric orbit with a period of 100 days. Its γ-velocity
is close to the constant radial velocity of the visual primary, confirming the physical association of the stars. 相似文献
102.
This work is basically concerned with grain nucleation occurring in protostellar envelopes. On the basis of the dissociation equilibrium theory, molecular and atomic abundances are obtained for massive protostar envelopes. Application of time-independent homogeneous nucleation theory results in the possibility of atomic Fe condensation. 相似文献
103.
—We have developed and operated optical fiber interferometers for monitoring displace ments within boreholes, as part of a program of crustal deformation measurement. These optical fiber strainmeters—a total of twelve instruments at two sites in southern California—were installed to sense the motion of the end-monuments of much longer baseline strainmeters and tiltmeters, allowing correction for any near-surface ground movement. One of the installations was specifically designed to investigate the distribution of deformation with depth, measuring over several borehole length-intervals from 5 m to 50 m. The displacements recorded over year-long time scales along these length intervals range up to 6 mm and show internal consistency and stability at the 50 μ m level. The use of these interferometers to provide correction signals for kilometer-scale crustal strain measurements has resulted in greatly improved records. 相似文献
104.
The paper proposes a method for studying long-term anomalies of the radon concentration that are produced by an impulse generated in a fracture source over a finite time interval. Using this method, experimental data are interpreted numerically in order to determine the space-time characteristics of the fracture region and parameters of fluid migration. 相似文献
105.
Results of numerical simulations using the WRF-ARW nonhydrostatic model are presented for eight episodes of intense convection over European Russia in the summer of 2007. The calculations were performed on four nested grids with horizontal grid meshes of 27, 9, 3, and 1 km. Convection was parametrized on the first two grids and explicitly resolved on the other two. It has been found that simulations on finer grids with explicit calculation of convective flows make it possible to reproduce heavy rainfalls and strong-wind zones in the areas of intense convection. A preliminary verification of the short-range predictions of convective systems shows that the maximum 12-h precipitation totals and the maximum winds at 10 m are close, in the order of magnitude, to the observed values. Prediction of convection centers is the weakest point. Difficulties in the model verification associated with the absence of data with high space-time resolution are discussed. 相似文献
106.
107.
Natural Resources Research - Sand failure and production occurs when the formation stress exceeds the strength of the formation, which is derived majorly from the natural material that cements the... 相似文献
108.
109.
110.
Relationships among conductivity, temperature, total dissolved solids (TDS), and density were determined for hypersaline brine
(TDS, 83 g kg−1) from Mono Lake. A theoretical estimate of density based on ionic composition and calculated partial molar volumes compared
well with actual measurements (difference, 390 ppm). However, an empirically derived equation of state based on temperature
and conductivity provides the most accurate density estimates (residual errors, 190 ppm) and can be used with data collected
with CTD profilers. 相似文献