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1.
Astronomy Letters - The emission from the Crab nebula exhibits a significant gamma-ray variability. In this paper we have analyzed this variability in terms of periodicity. Using the pulsar... 相似文献
2.
Hydrological trends and the evolution of catchment research in the Alptal valley,central Switzerland
Manfred Stähli Jan Seibert James W. Kirchner Jana von Freyberg Ilja van Meerveld 《水文研究》2021,35(4):e14113
When the observation of small headwater catchments in the pre-Alpine Alptal valley (central Switzerland) started in the late 1960s, the researchers were mainly interested in questions related to floods and forest management. Investigations of geomorphological processes in the steep torrent channels followed in the 1980s, along with detailed observations of biogeochemical and ecohydrological processes in individual forest stands. More recently, research in the Alptal has addressed the impacts of climate change on water supply and runoff generation. In this article, we describe, for the first time, the evolution of catchment research at Alptal, and present new analyses of long-term trends and short-term hydrologic behaviour. Hydrometeorological time series from the past 50 years show substantial interannual variability, but only minimal long-term trends, except for the ~2°C increase in mean annual air temperature over the 50-year period, and a corresponding shift towards earlier snowmelt. Similar to previous studies in larger Alpine catchments, the decadal variations in mean annual runoff in Alptal's small research catchments reflect the long-term variability in annual precipitation. In the Alptal valley, the most evident hydrological trends were observed in late spring and are related to the substantial change in the duration of the snow cover. Streamflow and water quality are highly variable within and between hydrological events, suggesting rapid shifts in flow pathways and mixing, as well as changing connectivity of runoff-generating areas. This overview illustrates how catchment research in the Alptal has evolved in response to changing societal concerns and emerging scientific questions. 相似文献
3.
Astronomy Letters - To explain the presence of early X-ray emission from the object AT2018cow, we have studied a scenario with the presence of dense ejecta in the system in the equatorial plane.... 相似文献
4.
Cheptsov V. S. Belov A. A. Vorobyova E. A. Pavlov A. K. Tsurkov D. A. Frolov D. A. Lomasov V. N. Chumikov A. E. 《Solar System Research》2021,55(5):383-388
Solar System Research - Ionizing radiation is one of the main factors that destroy biomolecules in extraterrestrial conditions. The effects of radiation depend on the conditions of the exposure... 相似文献
5.
Astronomy Letters - We consider the spatial restricted circular three-body problem in the nonresonant case. The massless body (satellite) is assumed to have a large sail area and, therefore, the... 相似文献
6.
Izmailov I. S. Shakht N. A. Polyakov E. V. Gorshanov D. L. Pogodin M. A. 《Astrophysics》2021,64(2):160-171
Astrophysics - This paper is a continuation of our earlier work devoted to determining the orbit and mass of the star 61 Cyg and the changes in the photometric characteristics of its components.... 相似文献
7.
Acta Geochimica - The article presents the results of a comparative geochemical study of cherts and siliceous–clayey rocks composing the tectono-sedimentary complexes of various structural... 相似文献
8.
Kaptein Steven J. van de Wal Koen J. Kamp Leon P. J. Armenio Vincenzo Clercx Herman J. H. Duran-Matute Matias 《Ocean Dynamics》2020,70(1):41-56
Ocean Dynamics - One-dimensional models of exchange flows driven by horizontal density gradients are well known for performing poorly in situations with weak turbulent mixing. The main issue with... 相似文献
9.
Solar System Research - The possibility of determining the thermophysical characteristics of the lunar soil by a penetrating probe when using solar heat as a heater is considered. The effectiveness... 相似文献
10.
Selin V. A. Emelyanov A. A. Sizov O. S. Emelyanov K. S. Borisov A. V. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(9):1182-1189
Izvestiya, Atmospheric and Oceanic Physics - Our survey of various space image consumers identified that the geographic coverage, regularity, and frequency of observations are the most important... 相似文献