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151.
J. Leliwa‐Kopystyński M. J. Burcheli I. Włdarczyk 《Meteoritics & planetary science》2009,44(12):1929-1935
Abstract— Criteria for finding asteroid families (Zappala et al. 1995) are applied to a large (205,770 member) data set of asteroid orbital elements. The cases of the Eunomia and Themis families are considered as examples. This is combined with the cratering criteria for catastrophic disruption of small bodies in the solar system (Leliwa‐Kopystyński et al. 2008). We find that the Eunomia parent body itself was not catastrophically disrupted in the family‐generating impact event; after impact, the current body contains as much as 70% of its primordial mass. However, by contrast with Eunomia, the present mass of 24 Themis is only about 21% of that of its primordial body. Limits are placed on the sizes of the impactors in both examples, and for the case of Eunomia, the radius of the just sub‐critical crater (which may be present on 15 Eunomia) is predicted as <58 km. 相似文献
152.
Saskia E. Werners Zsuzsanna Flachner Piotr Matczak Maria Falaleeva Rik Leemans 《Global Environmental Change》2009,19(4):503-511
This paper discusses a recently proposed conceptualisation of ‘earth system governance’ by applying it to floodplain management in the Hungarian Tisza river basin. By doing so it aims to improve our understanding of governance systems facilitating adaptation to a changing world. The conceptualisation of earth system governance consists of three elements: problem structure, principles and research challenges. These three elements are assessed using results from actor interviews and policy review. A regional example of natural resources management is found to be a valid case for earth system governance research. The proposed conceptualisation of earth system governance explains well the main problems, barriers and opportunities for adapting floodplain management to climate change in the Tisza region. Problem structure analysis highlights how previous socio-economic and political orders continue to shape expectations and patterns of conduct. Current barriers can be attributed to a lack of the key governance principles credibility, stability, inclusiveness and adaptiveness. Interviewees perceived the lack of credibility and effective cooperation between organisations as the largest barrier. The research challenges proposed for earth system governance agree well with opportunities identified for adapting Tisza floodplain management, calling for inclusion of actors beyond governments and state agencies, and equitable resource allocation in particular. The analysis suggests that an additional challenge for earth system governance is the prioritisation of actions to support an existing governance system and its actors in adapting. 相似文献
153.
Zenon Nieckarz Andrzej Kuak Stanisaw Ziba Marek Kubicki Stanisaw Michnowski Piotr Baraski 《Atmospheric Research》2009,91(2-4):184-187
This work presents the results of a comparison between the global storm activity rate IRS and electric field intensity E0Z. The permanent analysis of the IRS may become an important tool for testing Global Electric Circuit models. IRS is determined by a new method that uses the background component of the first 7 Schumann resonances (SR). The rate calculations are based on ELF observations carried out in 2005 and 2006 in the observatory station “Hylaty” of the Jagiellonian University in the Eastern Carpathians (Kułak, A., Zięba, S., Micek, S., Nieckarz, Z., 2003. Solar variations in extremely low frequency propagation parameters: I. A two-dimensional telegraph equation (TDTE) model of ELF propagation and fundamental parameters of Schumann resonances, J. Geophys. Res., 108, 1270, doi:10.1029/2002JA009304). Diurnal runs of the IRS rate were compared with diurnal runs of E0Z amplitudes registered at the Earth's surface in the Geophysical Observatory of the Polish Academy of Sciences in Świder (Kubicki, M., 2005. Results of Atmospheric Electricity and Meteorological Observations, S. Kalinowski Geophysical Observatory at Świder 2004, Pub. Inst. Geophysics Polish Academy of Sciences, D-68 (383), Warszawa.). The days with the highest values of the correlation coefficient (R) between amplitudes of both observed parameters characterizing atmosphere electric activity are shown. The seasonal changes of R, IRS and E0Z are also presented. 相似文献
154.
Twenty-five fans in NE Poland, formed under subaerial terminoglacial (previously called ice-contact) conditions, were investigated to model the dominant genetic processes involved. These fans show, as do other types, a proximal, a middle and a distal subenvironment. It is found, however, that the characteristics of these subenvironments as present in subaerial terminoglacial fans differ in several respects from those in fans formed under other climatic conditions. The present study deals with the middle and distal subenvironments. These appear to be much less complex than the proximal subenvironment in this type of fan. The middle terminoglacial fan comprises two sandy facies, characterized by unchannelized transport (mainly sheet floods) and stream flows. The distal terminoglacial fan is characterized by one (sandy/silty) facies, resulting from unchannelized currents and from settling in ephemeral ponds; braided streams play a secondary part in this fan subenvironment. The characteristics of the middle and distal fan subenvironments are described and illustrated, as is the facies from the distal subenvironment. Their vertical and lateral relationships are presented in a facies model. 相似文献
155.
Sabina Spandowska Barbara Ŀubieńska Stanisŀaw Koŀaczkowski 《Aquatic Sciences - Research Across Boundaries》1973,35(2):278-285
The toxic influence of phenol, aniline, pyridine and chrome, substances often found in municipal wastewaters, on the bacteriaEscherichia coli andPseudomonas fluorescens was examined. The non-toxic, growth limiting, toxic and lethal doses were determined on the basis of observations made ofE. coli andP. fluorescens reproduction and respiration patterns. Comparative test series were set up with the various doses in different nutrient cultures to ascertain whether the bacterias’ multiplication process or carbohydrate decomposition was more sensitive to the chemicals. 相似文献
156.
157.
158.
Piotr Tucholka 《Earth and Planetary Science Letters》1980,48(2):379-384
A simple method of calculating running means over different intervals within palaeomagnetic records has been used to identify short-period secular variations of the geomagnetic field. The records from Polish lake sediments reveal variations in declination with a period between 290 and 372 years. The periodicity of variations in the inclination has been estimated to be between 522 and 670 years. 相似文献
159.
M. Jeleńska M. Kądziałko-Hofmokl J. Kruczyk S. A. Vincenz 《Pure and Applied Geophysics》1978,117(4):784-794
Summary Laboratory investigations of thermomagnetic properties of specimens from seven diabase dikes of South Spitsbergen have been performed. Studies of temperature variation of isothermal saturation remanence combined with Hopkinson effect measurements and investigations of low temperature remanence give information on the mineral composition of the magnetic phases present in the magnetic fraction of the diabases. The experiments show that the clean natural remanence of these dikes has been acquired at the time of their, consolidation in the Late Mesozoic, though three of them may have been partially remagnetized at the time of Tertiary orogeny. Since the dikes reveal several normal and reversed directions of clean natural remanence, it is concluded that they were formed at different times in the Late Mesozoic, even though some of them may have been subjected to secondary influences at a later date. 相似文献
160.