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911.
912.
913.
914.
Analysis of Argo float trajectories at 1 000 m and temperature at 950 m in the North Atlantic between November 2003 and January 2005 demonstrates the existence of two different circulation modes with fast transition between them. Each mode has a pair of cyclonic - anticyclonic gyres. The difference is the location of the cyclonic gyre. The cyclonic gyre stretches from southeast to northwest in the first mode and from the southwest to the northeast in the second mode. The observed modes strongly affect the heat and salt transport in the North Atlantic. In particular, the second mode slows down the westward transport of the warm and saline water from the Mediterranean Sea. 相似文献
915.
HD 10009 is a spectroscopic and speckle interferometric binary with almost identical solar-type components. It was studied via speckle interferometry using the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences and had its spectrophotometry performed in the 3500–9600 Å wavelength interval with the 2-m telescope of the Terskol Branch of the Institute of Astronomy of the Russian Academy of Sciences. A detailed analysis of the atmosphere of the primary component (component 1) of the binary yielded the abundances of some of the elements. The luminosities and temperatures of the components are found to be L 1= 2.9 L ⊙, L 2= 1.0 L ⊙ and T eff1=6017 K, T eff2=5930 K, respectively. The iron abundance is [Fe]=?0.27±0.05. Our results make it possible to assess the evolutionary status of the system. The binary is 7.9 Gyr old and the primary component is close to become a red giant, whereas the secondary component is still in the hydrogen-burning stage near the main sequence. 相似文献
916.
Some attempts of polarimetric sounding of Comet Halley will be undertaken from the flyby probes. In order to facilitate the final planning and the future interpretation of these experiments we have done a thorough analysis of practically all available polarimetric observations. An emphasis is made on interpretation attempts and their discussion. The results of the phase dependence of polarization investigations are presented covering a wide range of phase angles . The chief peculiarities of this dependence are: maximum polarization at = 90, diminishing through zero at 20, negative values up to several per cent and a final growth to zero at zero . A division into gaseous and dusty comets on polarimetric basis is revealed. The wavelength dependence of polarization is discussed. The numerous results of detailed polarimetry are compared to the negative results of attempts to detect the elliptical polarization. New observational problems arising from the evidence given by the negative polarization at small phase angles and by the opposition effect recently discovered are discussed. 相似文献
917.
We study the structure of electromagnetic field of slowly rotating magnetized star in a Randall-Sundrum II type braneworld.
The star is modeled as a sphere consisting of perfect highly magnetized fluid with infinite conductivity and frozen-in dipolar
magnetic field. Maxwell’s equations for the external magnetic field of the star in the braneworld are analytically solved
in approximation of small distance from the surface of the star. We have also found numerical solution for the electric field
outside the rotating magnetized neutron star in the braneworld in dependence on brane tension. The influence of brane tension
on the electromagnetic energy losses of the rotating magnetized star is underlined. Obtained “brane” corrections are shown
to be relevant and have non-negligible values. In comparison with astrophysical observations on pulsars spindown data they
may provide an evidence for the brane tension and, thus, serve as a test for the braneworld model of the Universe. 相似文献
918.
Jason A. McLennan Weishan Ren Oy Leuangthong C. V. Deutsch 《Natural Resources Research》2006,15(2):119-127
The application of steam-assisted gravity drainage (SAGD) to recover heavy oil sands is becoming increasingly important in
the northern Alberta McMurray Formation because of the vast resources/reserves accessible with this mechanism. Selecting the
stratigraphic elevations of SAGD well pairs is a vital decision for reservoir evaluation and planning. The inherent uncertainty
in the distribution of geological variables significantly influences this decision. Geostatistical simulation is used to capture
geological uncertainty, which is used can be transformed into a distribution of the best possible well pair elevations.
A simple exhaustive calculation scheme is used to determine the optimum stratigraphic location of a SAGD well pair where the
recovery R is maximized. There are three basic steps to the methodology: (1) model the uncertainty in the top continuous bitumen (TCB)
and bottom continuous bitumen (BCB) surfaces, (2) calculate the recovery at all possible elevation increments within the TCB
and BCB interval, and (3) identify the elevation that maximizes R. This is repeated for multiple TCB/BCB pairs of surfaces
to assess uncertainty. The methodology is described and implemented on a subset of data from the Athabasca Oilsands in Fort
McMurray, Alberta. 相似文献
919.
920.
V. M. Kotlyakov A. A. Lyutyy A. A. Velichko N. N. Dreyer I. N. Il'yina I. I. Spasskaya 《地理信息系统科学与遥感》2013,50(1):20-30
This article examines the objectives, structure, content, and scientific significance of three new major world atlases being prepared for publication by the Institute of Geography of the USSR Academy of Sciences in cooperation with other organizations. Translated from: Izvestiya Akademii Nauk SSSR, seriya geograficheskaya, 1988, No. 3, pp. 22-30 by Jay K. Mitchell, PlanEcon, Inc., Washington, DC 20005. 相似文献