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141.
B. Loupias E. Falize M. Koenig S. Bouquet N. Ozaki A. Benuzzi-Mounaix C. Michaut M. Rabec le Goahec W. Nazarov C. Courtois Y. Aglitskiy A. YA. Faenov T. Pikuz 《Astrophysics and Space Science》2007,307(1-3):103-107
We present experiments performed with the LULI2000 nanosecond laser facility. We generated plasma jets by using specific designed
target. The main measured quantities related to the jet such as its propagation velocity, temperature and emissive radius
evolution are presented. We also performed analytical work, which explains the jet evolution in some cases. 相似文献
142.
We present models of temperature distribution in the crust of a neutron star in the presence of a strong toroidal component
superposed to the poloidal component of the magnetic field. The presence of such a toroidal field hinders heat flow toward
the surface in a large part of the crust. As a result, the neutron star surface presents two warm regions surrounded by extended
cold regions and has a thermal luminosity much lower than in the case the magnetic field is purely poloidal. We apply these
models to calculate the thermal evolution of such neutron stars and show that the lowered photon luminosity naturally extends
their life-time as detectable thermal X-ray sources.
Work partially supported by UNAM-DGAPA grant #IN119306. 相似文献
143.
It was shown in an earlier paper that preferred hemispheres of solar activity alternate with the 22-year magnetic cycle, when analyzed in the 27.0 day Bartels rotation. Using data which cover the time between 1818 and 1983 we trace back this result to 1880 (cycle 12). Before 1880 no significant correlations are found. 相似文献
144.
The angular rotation velocities of stable, recurrent sunspots were investigated using data from the Greenwich Photoheliographic Results 1940 until 1968. We found constant rotation velocities during the passages on the solar disk with errors of about ±4 m s–1. During their lifetime these spots show a decreasing braking of their rotation velocities from 0.8 to 0.3 m s–1 per day. A plausible interpretation is found by assuming the spots to be coupled to a slowly rising subsurface flux tube and a rotation velocity which increases with depth.Mitteilungen aus dem Kiepenheuer-Institut Nr. 201. 相似文献
145.
Manfred Sthli Lars Nyberg Per‐Erik Mellander Per‐Erik Jansson Kevin H. Bishop 《水文研究》2001,15(6):927-941
A physically based SVAT‐model was tested with soil and snow physical measurements, as well as runoff data from an 8600 m2 catchment in northern Sweden in order to quantify the influence of soil frost on spring snowmelt runoff in a moderately sloped, boreal forest. The model was run as an array of connected profiles cascading to the brook. For three winter seasons (1995–98) it was able to predict the onset and total accumulation of the runoff with satisfactory accuracy. Surface runoff was identified as only a minor fraction of the total runoff occurring during short periods in connection with ice blocking of the water‐conducting pores. Little surface runoff, though, does not mean that soil frost is unimportant for spring runoff. Simulations without frost routines systematically underestimated the total accumulated runoff. The possibility of major frost effects appearing in response to specific combinations of weather conditions were also tested. Different scenarios of critical initial conditions for the winter, e.g. high water saturation and delayed snow accumulation leading to an increased frost penetration, were tested. These showed that under special circumstances there is potential for increased spring runoff due to soil frost. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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147.
Melting and subsolidus reactions in the system K2O-CaO-Al2O3-SiO2-H2O: corrections and additional experimental data 总被引:2,自引:0,他引:2
Melting relationships in the system K2O-CaO-Al2O3-SiO2-H2O have been reinvestigated using Schreinemakers analysis and hydrothermal experiments. The reaction sanidine+muscovite+zoisite+quartz+vapor =melt has been bracketed at 10, 15, and 20 kbars and 670–680, 680–690, and 690–700° C, respectively and it marks the lowest solidus temperatures in the system investigated.Below 10 kbars, experimental data on the beginning of melting in zoisite- or muscovite-bearing anorthite+sanidine assemblages have been obtained, which are not showing any differences and therefore point to melt compositions close to the feldspar-quartz join. 相似文献
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