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941.
K.L. Majumder R. Ramakrishnan I.C. Matieda G. Sharma A.K.S. Gopalan D.S. Kamat 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(2):283-286
Indian Space Research Organisation (ISRO) plans to launch a Remote Sensing Satellite around 1985 for acquiring resources information in the visible and near infrared region. For this a number of projects under Joint Experiments Program (JEP) were taken up between ISRO and various departments under Government of India to define the mission parameters including the spectral bands. This paper presents the results obtained in the selection of spectral bands and their widths for IRS program. 相似文献
942.
D.K. Kondepudi I. Prigogine 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(5):171-176
We note that far-from-equilibrium chemical systems can respond very sensitively to gravity. The response could be in selection of possible structures or in the formation of propagating bands. In these cases the sensitivity is characterized by the factor , where n=2 or 3, Eg the interaction energy, k the Boltzmann constant and T, the temperature. Also, taking the thermodynamic fluctuations into account, we obtain the theoretical limit for the minimum field strength measurable by such systems. 相似文献
943.
V.I. Polezhaev S.A. Nikitin A.I. Fedyushkin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(5):65-78
Investigations conducted earlier by the authors have established that due to the steady-state field of body forces, convection is capable of giving rise to macroinhomogeneity in transverse impurity distribution in crystals. In the case of semiconductor materials the maximal value of this inhomogeneity is due to a weak convection in the melt, typical of low-gravity conditions. However, in addition to steady gravitational convection, other factors ignored previously, may also be employed in conducting experiments in low-g environments. The present paper discusses the results of theoretical studies of some factors influencing impurity distribution in the melt and the crystal. 相似文献
944.
945.
This issue of the journal contains papers with the results of studying gravitationally sensitive systems and processes under conditions of microgravity aboard the Mirorbital complex. This is one of the most difficult field of space research whose difficulties are due to both complexity of the object of investigations (since the class of gravitationally sensitive systems and processes is fairly wide, and some of them are not sufficiently studied even under terrestrial conditions) and necessity of using expensive instrumentation and carrying out long-term experiments. However, studying the new mechanical state of weightlessness is inevitable in space exploration. In addition, in some cases it can provide for a new knowledge about the fundamental laws of nature. By virtue of the above reasons, the experiments on microgravity are well presented in the research program onboard the International Space Station.There is a long tradition in this field of research in Russia, and the experience of Russian scientists (a part of which is presented in the papers of this issue) allows them to pass on to the next, better technically equipped, stage of investigations in cooperation with the scientists from other countries.This issue is prepared by an initiative of the subsection Mechanics of zero gravity and gravitationally sensitive systemsof the Coordination Scientific and Technical Council (CSTC) of the Russian Agency for Aviation and Space Flights (Rosaviakosmos). 相似文献
946.
Experimental results are reported for small signal gain distribution across a cavity of a mixed flow gasdynamic laser system at different turbulent supersonic mixing regimes. It is shown that the temperature range of the GDL generation regime can be extended up to 7000°K, and gain coefficients as high as 3.5 m−1 be attained in a “double-freeze” supersonic gas flow. Basic advantages are discussed as well as the opportunity to obtain higher efficiencies in thermally pumped laser systems. 相似文献
947.
Savina VP Mikos KN Ryzhkova VE Gorshunova AI Nefyodov YG Lepsky AA Aksyonov VV 《Acta Astronautica》1979,6(10):1251-1254
The Soyuz 22 space cabin atmosphere was studied for volatile organic trace contaminants. By gas chromatography the following constituents were identified: methane, ethane, heptane, methanol, ethanol, n-propanol, acetaldehyde, acetone, ethyl benzene. Except for acetone, concentrations of the above compounds were close to the values determined in the mock-up experiments. 相似文献
948.
L.V. Zasova V.A. Krasnopolsky V.I. Moroz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(9):13-16
It is shown that decline of spherical albedo of Venus toward the ultraviolet can be explained by the presence of two absorbing agents: a) SO2, for which abundance is 1011 cm?3 at height 68 km and scale height is about 1 km; b) some unknown aerosol absorbent, possibly a 1% FeCl3 admixture in a sulfuric acid concentrated solution. A mechanism of aerosol formation is proposed. 相似文献
949.
R.A. Harrison A. Fludra E.C. Sawyer J.L. Culhane K. Norman A.I. Poland W.T. Thompson O. Kjeldseth-Moe B. Aschenbach M.C.E. Huber A.H. Gabriel H.E. Mason 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(12):2239-2248
We present first results from the Coronal Diagnostic Spectrometer (CDS) aboard the ESA/NASA Solar and Heliospheric Observatory (SOHO). CDS is a double spectrometer operating in the 151–785 Å range. This region of the solar spectrum is rich in emission lines from trace elements in the solar atmosphere, which can be used to derive diagnostic information on coronal and transition region plasmas. Early spectra are presented and well identified lines are listed. In addition, examples of images in selected wavelength ranges are shown, for a prominence, a loop system and a bright point, demonstrating well the power of such extreme ultraviolet observations. 相似文献
950.