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101.
A. D. Kuzmin 《Astrophysics and Space Science》2007,308(1-4):563-567
We present a brief review of observational manifestations of pulsars with giant pulses radio emission, based on the survey
of the main properties of known pulsars with giant pulses, including our detection of 4 new pulsars with giant pulses. 相似文献
102.
Giant pulses have been detected from the pulsar PSR B0031-07. A pulse with an intensity higher than that of the average pulse by a factor of 50 or more is encountered approximately once per 300 observed periods. The peak flux density of the strongest pulse was 530 Jy, which is a factor of 120 higher than the peak flux density of the average pulse. The giant pulses are a factor of 20 narrower than the integrated profile and are clustered about its center. 相似文献
103.
Because of the absence of the atmosphere, the short duration of the Phobos day (7.7 hours), and the presence of a highly porous and fine-grained soil on the Phobos surface, all components of the future Russian Fobos–Grunt lander will operate under frequent and sharp temperature changes: from positive to extremely low negative temperatures. As a consequence, information about the temperature regime directly on the surface of the Martian satellite and in the near-surface layer appears to be extremely important. The proposed publication contains both the information about the thermophysical properties of the surface regolith of Phobos, derived from observations made with the Mariner 9 orbiter, the Viking orbiter, the Fobos-2 spacecraft, and the Mars Global Surveyor orbiter, and the results of the numerical modeling of the thermal regime of the surface regolith layer (on diurnal and seasonal time scales) in the area of the potential Fobos–Grunt landing site. We performed this modeling by taking into account the seasons on Mars and the effects due to the eclipse of Phobos by Mars. 相似文献
104.
A.E. Basharinov I.B. Drozdowskaya S.T. Egorov V.N. Galaktionov M.A. Kolosov V.D. Krotikov N.N. Kroupenio A.D. Kuzmin V.A. Lodygin L.I. Malafeev E.I. Omelchenko O.B. Schuko N.Y. Shapirovskaya A.M. Shutko V.S. Troitskiy Yu.N. Vetukhnovskaya 《Icarus》1972
A 3.4-cm wavelength radiometer aboard the Mars 2 and 3 orbiters observed the brightness temperature due to planetary thermal emission in two orthogonal polarizations as a function of position on Mars. Preliminary results for two orbits of Mars 3 show a correlation between subsurface temperature and dielectric constant, interpreted as an effect of porosity. 相似文献
105.
106.
107.
V. A. Kuzmin 《Russian Meteorology and Hydrology》2009,34(6):384-391
This paper initiates a series of three articles on automatic calibration of operational multi-parameter models used for flash flood forecasting in automated regime. The main point expressed in this series is that proper calibration of even a single model for a single basin is not a trivial problem, but in automated forecasting systems, when thousands or even millions of basins should be parametrized simultaneously, priorities change. Now the computational efficiency becomes the most critical; an implemented calibration procedure must be fast and efficient rather than giving “the best“ parameters yet computationally expensive. The first article of the series contains critical analysis of the “mainstream“ in hydrological models calibration and presents basic principles of the Stepwise Line Search algorithm and its modifications, practically feasible and robust parametrization approaches that would be suitable for automated systems used for flash flood forecasting. 相似文献
108.
N. A. Evdokimova R. O. Kuzmin A. V. Rodin A. A. Fedorova O. I. Korablev J. P. Bibring 《Solar System Research》2009,43(5):373-391
The results of the analysis of the spectral observations of Mars carried out with the OMEGA spectrometer onboard the Mars Express spacecraft are presented. The data from one of the spectrometer’s channels working in the near-IR spectral range (0.93–2.69
μm) were analyzed. This range includes the characteristic absorption bands of both condensed water phases (ice and frost)
and bound water contained in hydrated minerals of the Martial soil. From the 1.93-μm band indicating the presence of these
minerals, global maps of the bound-water index have been made. They show a noticeable latitude dependence of the index: the
largest values refer to high latitudes (>60°), while they gradually diminish toward the equator. Seasonal variations of the
spectral index obtained by the 1.93-μm band are connected with the hydration-dehydration processes occurring in hydrogenous
minerals when the temperature of the soil and the relative humidity in the near-surface atmospheric layer are changing. The
evolution of the spectral absorption bands of water ice (1.2 and 1.5 μm) dependent on the season testifies to the changes
in the microstructure of the surface layer in the North ploar cap caused by the sublimate re-crystallization processes in
the ice sheet. The spatial pattern of the location of the areas where the microstructure most quickly grows could be formed
under the influence of the stationary atmospheric waves. 相似文献
109.
David A. Williams Ronald Greeley Robin L. Fergason Ruslan Kuzmin Thomas B. McCord Jean-Phillipe Combe James W. Head Long Xiao Leon Manfredi François Poulet Patrick Pinet David Baratoux Jeffrey J. Plaut Jouko Raitala Gerhard Neukum 《Planetary and Space Science》2009,57(8-9):895-916
Building on previous studies of volcanoes around the Hellas basin with new studies of imaging (High-Resolution Stereo Camera (HRSC), Thermal Emission Imaging System (THEMIS), Mars Orbiter Camera (MOC), High-Resolution Imaging Science Experiment (HiRISE), Context Imager (CTX)), multispectral (HRSC, Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité (OMEGA)), topographic (Mars Orbiter Laser Altimeter (MOLA)) and gravity data, we define a new Martian volcanic province as the Circum-Hellas Volcanic Province (CHVP). With an area of >2.1 million km2, it contains the six oldest central vent volcanoes on Mars, which formed after the Hellas impact basin, between 4.0 and 3.6 Ga. These volcanoes mark a transition from the flood volcanism that formed Malea Planum ~3.8 Ga, to localized edifice-building eruptions. The CHVP volcanoes have two general morphologies: (1) shield-like edifices (Tyrrhena, Hadriaca, and Amphitrites Paterae), and (2) caldera-like depressions surrounded by ridged plains (Peneus, Malea, and Pityusa Paterae). Positive gravity anomalies are found at Tyrrhena, Hadriaca, and Amphitrites, perhaps indicative of dense magma bodies below the surface. The lack of positive-relief edifices and weak gravity anomalies at Peneus, Malea, and Pityusa suggest a fundamental difference in their formation, styles of eruption, and/or compositions. The northernmost volcanoes, the ~3.7–3.9 Ga Tyrrhena and Hadriaca Paterae, have low slopes, well-channeled flanks, and smooth caldera floors (at tens of meters/pixel scale), indicative of volcanoes formed from poorly consolidated pyroclastic deposits that have been modified by fluvial and aeolian erosion and deposition. The ~3.6 Ga Amphitrites Patera also has a well-channeled flank, but it and the ~3.8 Ga Peneus Patera are dominated by scalloped and pitted terrain, pedestal and ejecta flow craters, and a general ‘softened’ appearance. This morphology is indicative not only of surface materials subjected to periglacial processes involving water ice, but also of a surface composed of easily eroded materials such as ash and dust. The southernmost volcanoes, the ~3.8 Ga Malea and Pityusa Paterae, have no channeled flanks, no scalloped and pitted terrain, and lack the ‘softened’ appearance of their surfaces, but they do contain pedestal and ejecta flow craters and large, smooth, bright plateaus in their central depressions. This morphology is indicative of a surface with not only a high water ice content, but also a more consolidated material that is less susceptible to degradation (relative to the other four volcanoes). We suggest that Malea and Pityusa (and possibly Peneus) Paterae are Martian equivalents to Earth's giant calderas (e.g., Yellowstone, Long Valley) that erupted large volumes of volcanic materials, and that Malea and Pityusa are probably composed of either lava flows or ignimbrites. HRSC and OMEGA spectral data indicate that dark gray to slightly red materials (often represented as blue or black pixels in HRSC color images), found in the patera floors and topographic lows throughout the CHVP, have a basaltic composition. A key issue is whether this dark material represents concentrations of underlying basaltic material eroded by various processes and exposed by aeolian winnowing, or if the material was transported from elsewhere on Mars by regional winds. Understanding the provenance of these dark materials may be the key to understanding the volcanic diversity of the Circum-Hellas Volcanic Province. 相似文献
110.
A. A. Grechnikov A. S. Borodkov A. V. Pento N. B. Polyakov I. I. Kuzmin 《Geochemistry International》2017,55(1):19-26
Two new versions of surface-assisted laser desorption/ionization method are considered. One version is based on a combination of this method with thermal desorption sample injection and may be applied for determination of chemical compounds that are transformed into a gas phase without decomposition by heating. Another version is based on laser-induced electron-transfer desorption/ionization and could be used for determination of compounds with low proton affinity. The possibilities of the new approaches are illustrated by the example of determination of aminoacids, medical compounds, chlorophyll, as well as gold in sulfide ores. 相似文献