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611.
S M Kochubey O I Volovik L V Porubleva V V Shevchenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(8-9):1127-1130
The photosynthetic membrane composition and low temperature fluorescence spectra were analyzed for pea chloroplasts from control and clinostated plants. Clinorotation induces a decrease in the amount of the oligomeric form of the light-harvesting chlorophyll a/b complex (LHCII) and an increase of its monomeric form. Some changes in organization of photosystem 1 (PS1) complex were revealed as well. These changes are in accordance with the variations of fluorescence characteristics and photochemical activity. 相似文献
612.
Active Spacecraft Potential Control Investigation 总被引:1,自引:0,他引:1
K. Torkar R. Nakamura M. Tajmar C. Scharlemann H. Jeszenszky G. Laky G. Fremuth C. P. Escoubet K. Svenes 《Space Science Reviews》2016,199(1-4):515-544
613.
This paper explores the possibility of applying recent developments in various fields of electronics, especially wireless personal communication services, to reduce avionics systems repair cycle time and to generally improve maintenance services. But before scaling these prospects, present-day maintenance services are touched upon and advances in associated technologies are also mentioned 相似文献
614.
615.
616.
Large-scale Coronal Heating, Clustering of Coronal Bright Points, and Concentration of Magnetic Flux
By combining quiet-region Fe XII coronal images from SOHO/EIT with magnetograms from NSO/Kitt Peak and from SOHO/MDI, we show
that the population of network coronal bright points and the magnetic flux content of the network are both markedly greater
under the bright half of the large-scale quiet corona than under the dim half. These results (1) support the view that the
heating of the entire corona in quiet regions and coronal holes is driven by fine-scale magnetic activity (microflares, explosive
events, spicules) seated low in the magnetic network, and (2) suggest that this large-scale modulation of the magnetic flux
and coronal heating is a signature of giant convection cells.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
617.
A. N. Kusyumov E. V. Romanova A. S. Batrakov R. R. Nurmukhametov G. N. Barakos 《Russian Aeronautics (Iz VUZ)》2012,55(3):263-268
We consider a problem of a stationary incompressible viscous fluid flow around a flat circular cylinder. In the vicinity of the critical Reynolds number Re cr a stepwise drop of the cylinder drag takes place, which is called the drag crisis. 相似文献
618.
This paper presents the results of three-dimensional numerical studies of hydrodynamics and heat exchange on the models of flat plates in the jet airflow. These results are compared with the experimental data. A three-dimensional model for determining the thermal condition of the nozzle clusters in the conjugated formulation is proposed. Also presented are the data on optimization of the system used for the jet airflow around the duct platforms of the nozzle clusters. 相似文献
619.
G. Clément D. Hamilton L. Davenport B. Comet 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
This paper reviews the medical operations performed on six European astronauts during seven space missions on board the space station Mir. These missions took place between November 1988 and August 1999, and their duration ranged from 14 days to 189 days. Steps of pre-flight medical selection and flight certification are presented. Countermeasures program used during the flight, as well as rehabilitation program following short and long-duration missions are described. Also reviewed are medical problems encountered during the flight, post-flight physiological changes such as orthostatic intolerance, exercise capacity, blood composition, muscle atrophy, bone density, and radiation exposure. 相似文献
620.
R. Govind J.J. Valette F.G. Lemoine 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The Lambert–Amery System is the largest glacier–ice shelf system in East Antarctica, draining a significant portion of the ice sheet. Variation in ice sheet discharge from Antarctica or Greenland has an impact on the rate of change in global mean sea level; which is a manifestation of climate change. In conjunction with a measure of ice thickness change, ice sheet discharge can be monitored by determining the absolute velocities of these glaciers. 相似文献