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251.
Summary The Sava river annual precipitation field and the discharge anomalies in the Sava river catchment are compared to each other
and to mean sea-level pressure anomalies over Europe. In addition to a correlation analysis a clustering technique is used
for the time series from 1901–1990. Discharge data are available only for the period 1931–1990. As expected, a high correlation
exists between the Sava river discharge and precipitation, but also, remarkable correlation is found between air pressure
anomalies and Sava river precipitation. Grouping the years into four classes, the correlation is shown to be especially high
for extreme events. A possible application of these results might be for the downscaling of long-lead climate anomaly forecasts.
Received November 30, 1995 Revised May 21, 1998 相似文献
252.
Zlatko Majlinger Zoran Simić Milan S. Dimitrijević 《Journal of Astrophysics and Astronomy》2015,36(4)
The electron-impact widths for 27 Lu III spectral lines have been calculated by using the modified semiempirical method. Calculations have been also performed with the published relativistic Hartree-Fock oscillator strengths and additionally, with the approximate formula of Cowley. With the obtained results, the influence of Stark broadening on Lu III lines was investigated in the spectra of A-type stars. The obtained data will be included in the STARK-B database, which is part of the Virtual Atomic and Molecular Data Center – VAMDC. 相似文献
253.
Milan M. Ćirković 《Earth, Moon, and Planets》2002,91(4):243-254
We consider the little-known anthropic argument of Fontenelledealing with the nature of cometary orbits, given a year before the publication of Newton'sPrincipia. This is particularly interesting in view of the rapid development of therecently resurgent theories of cometary catastrophism and their role in the modern astrobiologicaldebates, for instance in the ``rare Earth' hypothesis of Ward and Brownlee. 相似文献
254.
Borna Lužar-Oberiter Tamás Mikes Hilmar von Eynatten Ljubomir Babić 《International Journal of Earth Sciences》2009,98(5):1097-1108
Cr-spinel is a common heavy mineral in the sandstones of Cretaceous synorogenic sedimentary formations of the NW Dinarides,
Croatia. The rocks occur in isolated exposures in the uplifted basement units of Medvednica, Ivanščica, Žumberak and Samobor
Mountains near Zagreb. In this area, evidence of the early Alpine evolution of the Dinarides is obscured due to strong dismemberment
of pre-Tertiary tectonostratigraphic units resulting from an intense tectonic history, as well as due to the widespread sedimentary
cover of the Pannonian Basin. Electron microprobe analyses of detrital Cr-spinels from the Oštrc Formation reveal that in
the Early Cretaceous the ophiolitic source area was predominantly composed of harzburgite peridotites and associated cumulate
rocks, which developed in a supra-subduction zone setting. The supply of Cr-spinels with the same chemical signature remained
dominant until the end of the Cretaceous, suggesting that exposed remnants of the same ophiolite belt persisted through the
Cretaceous and/or that recycling was significant. Similarities with data reported from the Northern Calcareous Alps and the
Transdanubian Central Range imply that a rather extensive harzburgitic ophiolite belt probably extended along the Adriatic
margin during the Early Cretaceous. A slight trend of increasing variation in the Cr# is observed from the Early to the latest
Cretaceous, suggesting that the source areas became more heterogeneous with the ongoing Cretaceous tectonic evolution. Differences
in Cr-spinel compositions in two contemporaneous latest Cretaceous formations are well in line with existing data on heavy
mineral proportions, which together identify contrasting hinterland geology for these formations and strongly suggest the
coeval existence of two separate basins.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
255.
Gregor Muri Branko Čermelj Radojko Jaćimović Dragomir Skaberne Andrej Šmuc Martina Burnik Šturm Janja Turšič Polona Vreča 《Journal of Paleolimnology》2013,50(4):457-470
Several geological and geochemical parameters were determined in the sediments of the 5th (5 J) and 6th (6 J) Triglav Lakes, Julian Alps (NW Slovenia), in order to study the impact of natural catchment characteristics and anthropogenic activity. Fish were introduced into both lakes in 1991 and a mountain hut lies on the shore of 5 J. Sedimentary grain size (GS) was distinctly coarser in 5 J than 6 J, with arithmetic means ranging between 46 and 60 and 23–36 μm, respectively. In contrast, the mineralogical composition of the two sediments was similar. Calcite predominated strongly, comprising more than 77 % of total minerals, while dolomite and quartz were rare. Organic carbon (OC) and total nitrogen (TN) concentrations were highest in surficial sediments, with levels of 14.4 and 1.8 %, and 19.3 and 2.4 % observed in 5 J and 6 J, respectively. C/N ratios (atomic) were lowest in the same surface sediments, with the two lakes characterized by similar values (9.6 vs. 9.4, respectively), suggesting a predominance of autochthonous organic matter (OM) in both lakes. Contemporary δ13C values were lower in 5 J (?21.0 ‰) than 6 J (?18.5 ‰) sediments. Considerable changes in these four parameters were observed in recently deposited material, reflecting a shift in the trophic status of both lakes that was likely induced by the introduction of fish. In addition, the smaller and shallower 6 J seemed to respond to changes faster than the larger and deeper 5 J, indicating the higher sensitivity of the former. δ15N values in surface sediments of 5 J and 6 J were ?2.9 and ?4.4 ‰, respectively, with levels increasing gradually with depth to approximately +1.0 ‰ in deeper sediments. The observed changes could most likely be attributed to the atmospheric deposition of reactive nitrogen. The mountain hut has seemingly not had a significant enough impact on the lakes to be recorded in their sediments. 相似文献
256.
Surface micro-layer (ML) samples were collected in different seasons over a long time period in the coastal area of the Middle Adriatic Sea including the seawater Rogoznica lake location and the semi-enclosed estuarine Martinska station. Natural surface micro-layers were studied as original samples and as ex-situ reconstructed films after previous extraction by organic solvents of different polarities (n-hexane and dichloromethane). Using alternating current (AC) voltammetry (out-of-phase mode) the concentration of surface active substances (SAS) in original ML of both locations was determined, and the enrichment factor (EF) in the ML was related to the underlayer water (ULW) samples collected at 0.5 m depth. Seasonal variability of SAS concentrations of the ML was observed at both locations. The ex-situ films were studied using a modified AC voltammetry method (out-of-phase mode) transferring an organic extract of natural micro-layers spread onto electrolyte from the air-water interface to the mercury electrode surface. The comparison of adsorption characteristics for model lipids of different polarities and those of transferred ex-situ reconstructed films has revealed that different types of lipid material were present in each ex-situ film of the same micro-layer. Additional characterization of the surface active material of natural MLs was carried out by AC voltammetry (in-phase mode) using cathodic reduction of cadmium ions as an indicator of permeability of different films adsorbed at the mercury electrode. The SAS of ML of both investigated locations induced an inhibition effect to the reduction of cadmium ions. Seasonal variations of inhibition have also been noticed. The electrochemical study contributed to the physicochemical characterization of the surface active matter of the surface micro-layer with the emphasis to the role of lipids which, although they represent a minor fraction of the total micro-layer organic material, contribute considerably to the micro-layer formation and stabilization at the air–water interface. 相似文献
257.
258.
Solar Physics - Observational data clearly indicate the presence of 3-min oscillations in sunspots in spectral lines covering a vast temperature range from the low chromosphere to those lines... 相似文献
259.
Gojko Djurašević 《Astrophysics and Space Science》1993,206(1):119-127
The paper is devoted to the actual problematics in the determination of orbital and physical parameters of active CB on the basis of the interpretation of photometric observations. One solves the problem in two stages: by obtaining a synthetic light curve in the case when the parameters of the corresponding CB model are given a priori (direct problem) and by determining the parameters of the given model for which the best fit between the synthetic light curve and the observations is achieved (inverse problem). In this paper, the above procedure is applied to a particular case of CB AG Vir. 相似文献
260.