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601.
The scheme variants of implementing the thermal protection against heat flows being generated by the body of a high-temperature
stationary gas turbine engine (GTE) are presented. The scheme of the experimental bench with a working section is given. Methodical
approaches to the heat transfer calculation at different variants of forced and natural convection organization and under
various operating conditions are described. The generalized results of the experiments carried out using a heat curtain being
generated by porous injection are presented. 相似文献
602.
N.A. Tikhomirova S.A. Ushakova Yu.A. Kudenko I.V. Gribovskaya E.S. Shklavtsova Yu.V. Balnokin L.G. Popova N.A. Myasoedov J.-B. Gros Ch. Lasseur 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
This study addresses the possibility of growing different halophytic plants on mineralized human urine as a way to recycle NaCl from human wastes in a bioregenerative life support system (BLSS). Two halophytic plant species were studied: the salt-accumulating Salicornia europaea and the salt-secreting Limonium gmelinii. During the first two weeks, plants were grown on Knop’s solution, then an average daily amount of urine produced by one human, which had been preliminarily mineralized, was gradually added to the experimental solutions. Nutrient solutions simulating urine mineral composition were gradually added to control solutions. NaCl concentrations in the stock solutions added to the experimental and control solutions were 9 g/L in the first treatment and 20 g/L in the second treatment. The mineralized human urine showed some inhibitory effects on S. europaea and L. gmelinii. The biomass yield of experimental plants was lower than that of control ones. If calculated for the same time period (120 d) and area (1 m2), the amount of sodium chloride taken up by S. europaea plants would be 11.7 times larger than the amount taken up by L. gmelinii plants (486 g/m2 vs. 41 g/m2). Thus, S. europaea is the better choice of halophyte for recycling sodium chloride from human wastes in BLSS. 相似文献
603.
K. Durga Prasad S.V.S. Murty 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
A Wireless Sensor Network for in situ probing of lunar water/ice is proposed. The mission scenario in single and multi-tier architectures for probing water in a permanently shadowed region of the Moon and different scenarios of exploration are discussed. The ideas presented in the paper are a positive assertion of feasibility for the sensor node hardware, given current levels of technological advancements. 相似文献
604.
P.L. Saranya K. VenkateshD.S.V.V.D. Prasad P.V.S. Rama RaoK. Niranjan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The pre-storm behavior of NmF2 and TEC over an equatorial station, Trivandrum (8.47°N, 76.91°E, dip 0.6°S) and a low latitude station, Waltair (17.7°N,83.3°E, dip 20°N) has been studied for a total of 18 strong geomagnetic storms with DST ? −100 nT. The simultaneous measurements of GPS-TEC and NmF2 over Trivandrum and Waltair during the period 2000–2005 have been considered for the present study. It is found that there is a substantial increase in NmF2 and TEC before the onset of the storm over Waltair, while the increase is not present at Trivandrum. The origin of pre-storm enhancements in electron density still remains unresolved owing to several conditions in their potential sources and occurrence mechanisms. In the present study an attempt is made to identify the possible mechanisms responsible for such enhancements in electron density of the F-region. 相似文献
605.
606.
V. Florinski A. Balogh J. R. Jokipii D. J. McComas M. Opher N. V. Pogorelov J. D. Richardson E. C. Stone B. E. Wood 《Space Science Reviews》2009,143(1-4):57-83
Properties of the heliospheric interface, a complex product of an interaction between charged and neutral particles and magnetic fields in the heliosphere and surrounding Circumheliospheric Medium, are far from being fully understood. Recent Voyager spacecraft encounters with the termination shock and their observations in the heliosheath revealed multiple energetic particle populations and noticeable spatial asymmetries not accounted for by the classic theories. Some of the challenges still facing space physicists include the origin of anomalous cosmic rays, particle acceleration downstream of the termination shock, the role of interstellar magnetic fields in producing the global asymmetry of the interface, the influence of charge exchange and interstellar neutral atoms on heliospheric plasma flows, and the signatures of solar magnetic cycle in the heliosheath. These and other outstanding issues are reviewed in this joint report of working groups 4 and 6. 相似文献
607.
Maxim L. Khodachenko Valerii V. Zaitsev Albert G. Kislyakov Alexander V. Stepanov 《Space Science Reviews》2009,149(1-4):83-117
Coronal loops, which trace closed magnetic field lines, are the primary structural elements of the solar atmosphere. Complex dynamics of solar coronal magnetic loops, together with action of possible subphotospheric dynamo mechanisms, turn the majority of the coronal loops into current-carrying structures. In that connection none of the loops can be considered as isolated from the surroundings. The current-carrying loops moving relative to each other interact via the magnetic field and currents. One of the ways to take into account this interaction consists in application of the equivalent electric circuit models of coronal loops. According to these models, each loop is considered as an equivalent electric LCR-circuit with variable inductive coefficients L, capacitance C, and resistance R, which depend on shape, scale, position of the loop with respect to neighbouring loops, as well as on the plasma parameters in the magnetic tube. Such an approach enables to describe the process of electric current dynamics in the groups of coronal loops, as well as the related dynamical, energy release and radiation processes. In the present paper we describe the major principles of LCR-circuit models of coronal magnetic loops, and show their application for interpretation of the observed oscillatory phenomena in the loops and in the related radiation. 相似文献
608.
The results of analyzing axisymmetric forced vibrations of an elastic circular sandwich plate connected with an elastic foundation under different surface loads are presented. The hypotheses of a broken normal are accepted to describe the kinematics of a package that is nonsymmetrical over the thickness. The analytical solutions of a problem for plates with a light filler are obtained and numerical analysis is carried out. 相似文献
609.
In the framework of the general theory for unsteady weakly disturbed fluid flows with free boundaries, a problem is solved to calculate a jet flow around the cascade of plates executing the harmonic oscillations. We developed a program that enables us for the first time to carry out systematic calculations of flow characteristics depending on arbitrary values of determining parameters. 相似文献
610.
Yu. F. Gortyshov V. M. Gureev R. Sh. Misbakhov I. F. Gumerov A. P. Shaikin 《Russian Aeronautics (Iz VUZ)》2009,52(4):488-490
We present the results of experimental studies of the fuel hydrogen additive influence on the characteristics of a gas-piston
engine converted for operation by natural gas under changes of an ignition advance angle (IAA). The results of investigations
were used to determine the influence of the hydrogen additive on the effective engine efficiency and fuel consumption under
IAA changes. 相似文献