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1.
This paper is a short review of publications on the influence that solar activity and geomagnetic disturbances (cosmic weather) have on physical-chemical systems. The effects of cosmic weather may some-times be detected by the presence of an uncontrolled factor in these experiments. Direct reactions to cosmic weather are reliably identified in quantitative observations over various test systems, mainly water solutions. The effects of cosmic weather are also found from the data obtained by monitoring some simple physical systems, including semiconductors. All these effects are either cosmic physical rhythms or they are easily registered sporadic heliogeophysical events (e.g., magnetic storms). There are convincing data that demonstrate the influence that cosmic weather has on the accident rate in various engineering and physical systems. Researchers are at odds on the physical nature of the main physical agent, but the contribution of electromagnetic fields to these processes is considered important.  相似文献   
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It is investigated whether conditions for melting can be temporarily created in the upper sub-surface parts of snow/ice-packs on Mars at subzero surface temperatures by means of the solid-state greenhouse effect, as occurs in snow- and ice-covered regions on Earth. The conditions for this possible temporary melting are quantitatively described for bolometric albedo values A = 0.8 and A = 0.2, and with model parameters typical for the thermo-physical conditions at snow/ice sites on the surface of present Mars. It is demonstrated by numerical modelling that there are several sets of parameters which will lead to development of layers of liquid water just below the top surface of snow- and ice-packs on Mars. This at least partial liquefaction occurs repetitively (e.g. diurnally, seasonally), and can in some cases lead to liquid water persisting through the night-time in the summer season. This liquid water can form in sufficient amounts to be relevant for macroscopic physical (rheology, erosion), for chemical, and eventually also for biological processes. The creation of temporary pockets of sub-surface water by this effect requires pre-existing snow or ice cover, and thus is more likely to take place at high latitudes, since the present deposits of snow/ice can mainly be found there. Possible rheologic and related erosion consequences of the appearance of liquid sub-surface water in martian snow/ice-packs are discussed in view of current observations of recent rheologic processes.  相似文献   
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It is shown that viscous liquid film flow (VLF-flow) on the surfaces of slopes of martian dunes can be a low-temperature rheological phenomenon active today on high latitudes. A quantitative model indicates that the VLF-flows are consistent with the flow of liquid brines similar to that observed by imaging at the Phoenix landing site. VLF-flows depend on the viscosity, dynamics, and energetics of temporary darkened liquid brines. The darkening of the flowing brine is possibly, at least partially, attributed to non-volatile ingredients of the liquid brines. Evidence of previous VLF-flows can also be seen on the dunes, suggesting that it is an ongoing process that also occurred in the recent past.  相似文献   
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Sublimation of water ice is more effective than evaporation of sorption water at the same temperature. Therefore, water in the form of ice must, over geologic time-scales, have left the upper martian surface (m-scale) at mid- and low-latitudes, leaving sorption water as a possible physical form of stable subsurface water. Adsorption water is “liquid-like” at these temperatures (in the sense of a 2D-liquid). This property is the reason for the specific importance of physisorbed water under martian conditions. It is shown that unfrozen adsorption water can cause numerous physical, chemical, and possibly also biological processes in the upper martian surface and may be responsible for a number of its properties.  相似文献   
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This paper reviews formal approaches to representing spatial knowledge about qualitative direction. Unlike geometric direction information, qualitative information does not employ numerical values but relies on comparison. The qualitative approach is often regarded as suitable for capturing commonsense concepts and thus is relevant to human-centered interfaces for spatial information systems. To establish a context for the work on qualitative direction, we preset a brief history of the development of qualitative temporal and spatial representations from different scientific perspectives. We identify main focal areas of these representations of spatial direction and propose a taxonomy. In the light of more than three decades of fruitful research, we obtain a map of formal representations that reveal interrelationships between different research strands in the field.  相似文献   
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The 22 meter thick marine carbonate Upper Oligocene series of Astrup (NW Germany) is correlated with the Chattian type section of Doberg. It indicates a more constrained palaeogeographical and biostratigraphical position ranging from the biozones of Chlamys (C.) decussata (upper Chattian A) to Chlamys (C.) semistriatus (lower Chattian C). The macrofauna can be subdivided into three main benthic communities: A. the ?coarse gravel spondylid beach fauna?? of the shore zone with ?pebble beach facies?? dominated by sessile brachiopods, large balanids, spondylids, oysters or small regular echinoids. Borings are common in pebbles; B. the ?glauconite fine gravel brachiopod-bryozoan littoral fauna?? of the shallow subtidal zone where a terebratulid/lithothamnid dominated fauna/flora is present. The rhodophyceans were most possibly anker stones and substrates for cirripeds and serpulids; C. the ?glauconite carbonate sand phytal fauna?? of the shallow subtidal zone with a rich benthic mollusc dominated fauna. Indirect evidence for seagrass and macroalgae occurs on the attachment negatives of balanids and oysters, and also on Cibicides foraminifera or bryozoans like Cellepora. The facies types along the Wiehengebirge Island and Teutoburger Wald Peninsula coasts of the southern Pre-North Sea Basin differ with respect to their benthic communities to that of the siliciclastic Leipziger and the Rhenish Bay facies.  相似文献   
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A. V. Bruns 《Solar physics》1991,133(1):89-94
Several results of the solar irradiance observations carried out with the IPHIR experiment on board the Soviet spacecraft within the PHOBOS Project are considered. The time variations of the power spectrum of 5-min solar oscillations is discussed. It is found that the lines are generated inhomogeneously in the spectrum as a whole. Each of the frequencies is excited separately at a definite time interval. The duration of active periods does not exceed 2 or 3 hours.  相似文献   
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Sedimentary basins in NW‐Germany and the Netherlands represent potential targets for shale gas exploration in Europe due to the presence of Cretaceous (Wealden) and Jurassic (Posidonia) marlstones/shales as well as various Carboniferous black shales. In order to assess the regional shale gas prospectivity of this area, a 3D high‐resolution petroleum system model has been compiled and used to reconstruct the source‐rock maturation based on calibrated burial and thermal histories. Different basal heat flow scenarios and accordingly, different high‐resolution scenarios of erosional amount distribution were constructed, incorporating all major uplift events that affected the study area. The model delivers an independent 3D reappraisal of the tectonic and thermal history that controlled the differential geodynamic evolution and provides a high‐resolution image of the maturity distribution and evolution throughout the study area and the different basins. Pressure, temperature and TOC‐dependent gas storage capacity and gas contents of the Posidonia Shale and Wealden were calculated based on experimentally derived Langmuir sorption parameters and newly compiled source‐rock thickness maps indicating shale gas potential of the Lower Saxony Basin, southern Gifhorn Trough and West Netherlands Basin.  相似文献   
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