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251.
Iwona Stan-Kłeczek 《Acta Geophysica》2008,56(4):1065-1073
The existence of cracks in a rock mass causes the reduction of seismic wave velocity and the anisotropy of seismic wave velocity, which is characteristic for rocks with preferred orientation of cracks. The present study concerns sedimentary rocks (sandstone, limestone) and igneous rocks (basalt, granite). Studying the relationship between seismic anisotropy and cracks anisotropy in rocks I was only interested in fractures perpendicular to the layering. This allowed me to calculate two-dimensional crack tensors and velocity tensors in planes parallel to the layer surface. An application of tensor calculus enables to take into account both geometry and orientation of cracks. The obtained results confirm that the directions of major axes of second-rank velocity tensor prove the relationship consistent with predictions of theoretical models. Owing to these dependences, seismic methods can be used to study the cracks anisotropy in rocks inaccessible for direct observations. 相似文献
252.
Nguyen Dinh Chau Paweł Jodłowski Stefan J. Kalita Paweł Olko Edward Chruściel Adam Maksymowicz Michał Waligórski Paweł Bilski Maciej Budzanowski 《Acta Geophysica》2008,56(2):505-517
The doses of gamma radiation, concentrations of radium isotopes in water and sediments, radon concentration and concentration
of alpha potential energy of radon decay products in the copper ore mine and in the mining region in the vicinity of Lubin
town in Poland are presented. These data served as a basis for the assessment of radiological hazard to the mine workers and
general public. The results of this assessment indicate that radiological hazard in the region does not differ substantially
from typical values associated with natural radiation background. The calculated average annual effective dose for copper
miners is 1.48 mSv. In general, copper ore mines can be regarded as radiologically safe workplaces. 相似文献
253.
M. Jeleńska A. Hasso-Agopsowicz M. Kądziałko-Hofmokl A. Sukhorada K. Bondar ZH. Matviishina 《Studia Geophysica et Geodaetica》2008,52(2):255-270
The paper concerns the complex study of pedogenic and magnetic characteristics of unpolluted soil profiles from Ukraine (3
profiles, of which two represent chernozem and one kastanozem) and Poland (1 profile of chernozem), all with loess parent
material. Two of the profiles were situated further south than the other two. The “southern” zone is characterized by lower
precipitation rate and higher annual temperatures than the “northern” zone. Depth variations of magnetic properties obtained
with various methods were compared with pedogenic characteristics. The common characteristic of all profiles is enhancement
of susceptibility in their upper parts related to the presence of superparamagnetic/ single-domain grains of maghemite/oxidized
magnetite of pedogenic origin. However, variations of magnetic characteristics measured down depth profiles differ between
profiles probably due to differences in climatic conditions and, perhaps, parent loess. 相似文献
254.
Paweł Wiśniewski Mariusz Kistowski 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):123-136
Agriculture is often not included in the baseline greenhouse gas (GHG) emission inventories created for local low carbon economy plans in Poland and other European countries. We therefore estimate the size of the carbon footprint from agricultural sources and indicate the share of agriculture in the total GHG emissions in selected Polish communes (LAU level 2). We propose a solution whereby local government units can estimate their carbon footprint independently and monitor the impact of actions taken to reduce emissions. The value of the carbon footprint from agriculture in the selected communes varies from .5 to 46.5 thousand Mg CO2eq/year, with a mean value of 12.6 thousand Mg CO2eq/year and a standard deviation of 11.4 thousand Mg CO2eq/year. Per capita, these values range from 10 kg CO2eq/year to 8.4 Mg CO2eq/year, with a mean of 1.1 Mg CO2eq/year and a standard deviation of 1.5 Mg CO2eq/year. In all communes, the contribution of agriculture to total emissions is at an average of 14% (values range from .2 to 57.4%). The obtained results confirm the appropriateness of including emissions from the agricultural sector and other related sources in low carbon economy plans. 相似文献
255.
256.
Temporal and spatial variability of extreme river flow quantiles in the Upper Vistula River basin,Poland
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Temporal and spatial variability in extreme quantile anomalies of seasonal and annual maximum river flows was studied for 41 gauging stations at rivers in the Upper Vistula River basin, Poland. Using the quantile perturbation method, the temporal variability in anomalies was analysed. Interdecadal oscillating components were extracted from the series of anomalies using the Hilbert‐Huang transform method. Period length, part of variance of each component, and part of unexplained variance were assessed. Results show an oscillating pattern in the temporal occurrence of extreme flow quantiles with clusters of high values in the 1960–1970s and since the late 1990s and of low values in the 1980s and at the beginning of the 1990s. The anomalies show a high variability on the right bank of the Upper Vistula River basin during the summer season with the highest values in catchments located in the western and south‐western parts of the basin. River flow extreme quantiles were found to be associated with large‐scale climatic variables from the regions of the North Atlantic Ocean, Scandinavia, Eastern Europe, Asia, and, to a lesser extent, the Pacific Ocean. Similarities between temporal variability of river flows and climatic factors were revealed. Results of the study are important for flood frequency analysis because a long observation period is necessary to capture clusters of high and low river flows. 相似文献
257.
Małgorzata Moczydłowska 《Precambrian Research》1981,15(1):63-74
Acid-resistant, organic-walled microfossils (acritarchs) are reported from Lower and Middle Cambrian rocks penetrated by borehole Okuniew IG-1 in the western Podlasie depression. The study showed the presence of 11 acritarch species previously known from coeval rocks in northeast Poland. The assemblage from the Okuniew borehole is compared with characteristic assemblages from other parts of the East European platform. 相似文献
258.
J. Ziółkowski 《Astrophysics and Space Science》1969,3(1):14-30
The evolution of close binary systems was followed for ten systems with the initial mass of the primary in the range 1–4M
and with different initial mass ratios and initial separations. A brief discussion of the evolution of the contact component is presented for two separate cases: when the primary reaches its Roche lobe during central hydrogen burning (case A) and after the exhaustion of hydrogen in the center (case B).The models obtained are compared with observed semi-detached systems separately for massive (with total mass greater than 5M
) and low mass (with total mass below 4M
) binaries. It is shown that the contact components of the observed massive binaries are probably burning hydrogen in the core. On the contrary, the majority of contact components of the observed low-mass binaries are burning hydrogen in the shell. The observed distribution of such binaries as a function of different luminosity excesses of contact components seems to indicate that their origin is connected with case A rather than with case B. 相似文献
259.
Summary Due to the 1997 summer flood, the Pomeranian and Gdańsk Bays were polluted with a significant amount of bacteriologically
contaminated Oder and Vistula rivers waters. The purpose of this study was to determine the sanitary state of both bays during
the flood and directly after it, the range of direction of distribution of the bacteriological contamination brought in by
Vistula and Oder waters. On the basis of examination results, the sanitary state of the bays waters was found to be worse,
particularly with regard to indicators: total bacterial number (at 20 °C and 37 °C) and Most Probable Number (MPN) of coliform
and faecal coliform bacteria. Bacteria of the Pseudomonas group(Pseudomonas aeruginosa, Pseudomonas fluorescens), Enterobacteriaceae group (m.in.Proteus vulgaris), as well as enterococci(Streptoccus) and staphylococci(Staphylococcus) were found in water samples from Pomeranian and Gdańsk Bays. In the Pomeranian Bay the waters spread to the west (due to
weather conditions), whereas in Gdańsk Bay they remained mainly in the coastal zone and then moved to the east. An improvement
in the sanitary state of both bay waters was observed at the end of August.
Zusammenfassung W?hrend des Sommer-Hochwassers 1997 wurden die Gew?sser der Pommerschen und der Danziger Bucht mit kontaminiertem Wasser aus
den Flüssen Oder und Weichsel verunreinigt. Ziel dieser Arbeit ist es, den Grad der bakteriellen Verunreinigungen durch einstr?mendes
Flu?wasser aus Oder und Weichsel in die Pommersche und die Danziger Bucht w?hrend des Hochwassers und direkt danach zu bestimmen.
Auf der Basis von Messungen wurde eine Vermehrung von Colibakterien im Wasser beider Buchten unter Berücksichtigung folgender
Indikatoren festgestellt: 1. Gesamtzahl an Bakterien (Wassertemperatur 20 °C and 37 °C) und 2. vermuteter Anteil von gesamtcoliformen
und f?kalcoliformen Bakterien. Die Wasserproben aus der Danziger und der Pommerschen Bucht enthielten sowohl F?ulnisbakterien(Pseudomonas aeruginosa, Pseudomonas fluorescens) als auch Bakterien aus der Gruppe der Enterobacteriaceae(Proteus vulgaris), Staphylokokken(Staphylococcus) und F?kalstreptokokken(Streptococcus). Infolge Wetterver?nderung verlagerte sich das kontaminierte Wasser aus der Pommerschen Bucht nach Westen. In der Danziger
Bucht hingegen blieb das kontaminierte Wasser zun?chst im Küstenbereich und verlagerte sich dann ostw?rts. Ende August wurde
eine Verbesserung der Wasserqualit?t in beiden Buchten ermittelt. 相似文献
260.