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61.
62.
Volcanic ash can disperse thousands of kilometres from the source volcano and provide valuable chronostratigraphic markers for palaeoclimate studies. We present new cryptotephra findings of historical and modern Icelandic eruptions in annually laminated lacustrine sediment records from several sites within a 570 km SW–NE transect across northern Poland. Sediments from the two lakes Wąsoskie and Szurpiły contain glass shards originating from the Plinian Askja ad 1875 eruption and showing bimodal, rhyolitic and dacitic affinities. A further cryptotephra finding in Lake Lubińskie suggests a potential origin from the Hekla ad 1845 eruption. These new findings extend the tephra dispersal map towards the south-east and provide valuable isochrons for the synchronisation of palaeoclimate proxy data at the termination of the Little Ice Age in central eastern Europe. Very low glass concentrations of modern cryptotephra in Lake Wąsoskie were potentially correlated with the Eyjafjallajökull ad 2010 eruption. Further findings in the uppermost sediments of lakes Szurpiły and Żabińskie in north-eastern Poland tentatively suggest other sources from either the Hekla and/or Kamchatkan volcanoes.  相似文献   
63.
Here we briefly report on the discovery of a new Fossil‐Lagerstätte locality, Owadów‐Brzezinki quarry (central Poland), which exposes Late Jurassic (Late Tithonian) carbonate sediments with an extremely fossiliferous horizon of lithographic‐type limestones. Numerous specimens of horseshoe crabs were found in association with an enormously rich assemblage of the soft‐shelled bivalves Corbulomima obscura and Mesosaccella sp., the remains of various fishes and marine reptiles, rare ammonites, crustaceans, land insects and pterosaurs. The uniqueness of this new locality lies in its very close stratigraphical relationship to one of the most famous Fossil‐Lagerstätte localities in the world—Solnhofen, in southern Germany, with approximately 2 Ma separating them. Marine and terrestrial creatures lived and died during the Late Jurassic both at Solnhofen (Hybonotum Zone) and in another area (Owadów‐Brzezinki quarry, Zarajskensis Subzone), under closely related environmental conditions. The small palaeogeographical distance separating these two locations enables, for the first time, an effective palaeobiological test of the pace of evolutionary speciation amongst different groups of organisms.  相似文献   
64.
Extensive research and increasing number of potential industrial applications made ionic liquids (ILs) important materials in design of new, cleaner technologies. Together with the technological applicability, the environmental fate of these chemicals is considered and significant efforts are being made in designing strategies to mitigate their potential negative impacts. Many ILs are proven to be poorly biodegradable and relatively toxic. Bioaugmentation is known as one of the ways of enhancing the microbial capacity to degrade xenobiotics by addition of specialized strains. The aim of current work was to select microbial species that could be used for bioaugmentation in order to enhance biodegradation of ILs in the environment. We subjected activated sewage sludge to the selective pressure of 1-methyl-3-octylimidazolium chloride ([OMIM][Cl]) and isolated nine strains of bacteria which were able to prevail in these conditions. Subsequently, we utilized axenic cultures (pure cultures) of these bacteria as well as mixed consortium to degrade this IL. In addition, we performed growth inhibition tests and found that bacteria were able to grow in 2 mM, but not in 20 mM solutions of [OMIM][Cl]. The biodegradation conducted by the isolated consortium was higher than conducted by the activated sewage sludge when normalized by the cell density, which indicates that the isolated strains seem specifically suited to degrade the IL.  相似文献   
65.
According to Madeley’s (2003) comparative framework of state–church relations in Europe, Poland is part of the historic Northeast-Southeast multi-confessional culture belt. The aim of this paper is to analyse the historic relationships between the Polish state and church in relation to this framework with special attention to the post-Second World War period and to the consequences for the Polish religious landscape. In contrast to the multi-confessionality of the historic Polish polities, after the Second World War Poland became a mono-confessional, Roman-Catholic country. Territorial changes, the resettlement of people and the annihilation of the Jewish population by the Nazis were responsible for this religious homogenisation. Consequently, the relationship between state and church was almost completely confined to the relationship with the Roman-Catholic Church. During the 45 years of communist dominance, that church became the largest public organisation independent of the state authorities and played the most important role in the struggle against the ‘atheisation’ of Polish society as a consequence of the strong support for the church by the majority of people. The post–1989 period is characterised by a liberalisation towards non-Catholic religious communities and – after an initial reluctance – a positive attitude of the Polish Roman-Catholic Church (strongly supported by the Polish Pope John Paul II) towards the Polish membership of the European Union.
Elżbieta Bilska-WodeckaEmail:
  相似文献   
66.
MichaŁek  G.  Ostrowski  M. 《Solar physics》2001,200(1-2):177-187
The spatial transport of charged particles in the presence of pure slab Alfvén waves, pure isotropic magnetosonic waves and their mixture is considered using Monte Carlo particle simulations. We show that the mean free path of solar cosmic ray protons strongly depends on the assumed spectrum and amplitude of MHD turbulence but much less on the type of the considered waves. It is demonstrated that, for realistic solar wind parameters, the presented wide range wave spectrum models can reproduce the observed mean free path in a particular SEP event but not in a wide range of rigidity characterized by the Palmer's `consensus'.  相似文献   
67.
Our VLA and Effelsberg radio polarization studies of the interacting and cluster galaxies (NGC 3627, NGC 4038/39, NGC 4254) show that magnetic fields could help us in understanding galaxy peculiar gas motions and cluster environmental effects. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
68.
We used two different methods of statistical analysis—cluster analysis and principal component analysis—to analyze the concentrations of principal chemical components (Si, Mg, Ca, Fe, Ni) and Co in ordinary chondrites. The analysis is based predominantly on published data (metadata). In total, chemical composition data from 646 ordinary chondrites were used in the statistical analysis. The aim of this analysis was to establish whether it would be possible or not to distinguish H, L, and LL chondrites based on the concentrations of major elements and Co in their bulk chemical compositions. It was also important to determine what conclusions such an analysis could enable to draw about matter differentiation in the formation environments of primordial parent bodies of particular ordinary chondrite groups (H, L, and LL). Another aim of the statistical analysis was to determine whether the distribution of Fe and Ni (with Co admixtures) is independent of petrographic types within particular groups of chondrites. This is of crucial importance for determining the distribution of FeNi(Co) ore occurrences in potential extraterrestrial deposits on modern asteroids—the sources of ordinary chondrites. The obtained results of statistical analyses confirmed that a clear-cut distinction between particular groups of ordinary chondrites is only possible for group H, while distinguishing L chondrites from LL chondrites is not always obvious. The results of the statistical analyses relating to the question of the possible existence of several primordial parent bodies (formation environments) of each group of ordinary chondrites are consistent with the results of contemporary astronomical spectroscopy research. What is particularly interesting is obtaining indications of the existence of common formation environments of the matter of L and LL chondrites, possibly on a few primordial parent bodies. The statistical analyses indicate that there is no correlation between the concentration of principal chemical components and the petrographic type of ordinary chondrites. This proves homogenous distributions of these elements within the parent bodies of each group of ordinary chondrites. Hence, the distribution of these elements in individual present-day asteroids is also homogenous.  相似文献   
69.
In this work, the GOCE satellite orbit is described in the aspect of perturbations in the Keplerian osculating elements. The perturbations come from the Earth and ocean tides, the gravitation of the Moon, the gravitation of the Sun, the gravitation of planets and Pluto, and the relativity effects. These perturbations are computed for the 30-day interval with a sampling of 2 min. To obtain the simulated orbit, the Cowell numerical integration method of 8th order is used. The first part of the work contains the root mean square (RMS) values of aforementioned perturbations due to the specified forces. The perturbations were compared taking into account their RMS characteristics.  相似文献   
70.
The thermodynamical stability of a newly observed wadsleyite II phase in the Mg2SiO4 system is studied by the density functional theory. The wadsleyite II equation of state has been derived. The phase boundaries of Mg2SiO4 polymorphs: wadsleyite, wadsleyite II and ringwoodite are studied using the quasi-harmonic approximation at high external pressures. Clapeyron slopes determined for wadsleyite II–ringwoodite and wadsleyite–wadsleyite II boundaries are 0.0047 and 0.0058 GPa/K, respectively. It is shown that the wadsleyite II phase is not thermodynamically preferred in the pure Mg2SiO4 system and will probably not occur between wadsleyite and ringwoodite phases.  相似文献   
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