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EN
The Karkonosze granite massif contains groundwater with various depths of flow systems. In the mountainous part, fresh water predominates, mainly of local flow, where as in the Jelenia Góra Basin thermal waters have been found, reaching the temperature of 97°C. In nine samples of groundwater representing different flow depths, we have described a variation in the parameters of the structure and biodiversity of prokaryotes (bacteria and archaea). The variability of prokaryotes is determined by pH, Eh, electrolytic conductivity and temperature of water.
PL
Dane to często najcenniejsza rzecz, jaką gromadzimy na naszych komputerach. Bez odpowiedniego zabezpieczenia danych algorytmami szyfrującymi, cenne dla nas informacje w przypadku dostania się w niepowołane ręce mogą zostać bezproblemowo wykorzystane. Artykuł przedstawia wybrane metody szyfrujące i funkcje skrótu dostępne w bibliotece Boucy Castle dla środowiska Java. Przedstawiona analiza dotyczy pomiaru prędkości generowania i weryfikacji 240 bitowej sygnatury dla algorytmów szyfrujących, natomiast dla funkcji skrótu analiza dotyczy szybkości działania funkcji. Z pośród badanych algorytmów szyfrowania i funkcji skrótu najszybsze okazały się AES i SHA1.
EN
The data is often the most valuable thing that we collect on our computers. Without proper data security with encryption our valuable information may be illegally used by an unauthorised person. The article presents selected encryption methods and hash functions available in Boucy Castle library for Java programming language. The presented analysis applies to measurement of the speed of signature generation and verification. The signatures are for 240 bit encryption algorithms. In case of a hash function, the analysis refers to the speed of such functions. The fastest encryption algorithm and hash function from the research group were AES and SHA1.
EN
The mineral framework and pore waters of glacial sediments exposed in the foreland of Weren- skioldbreen in SW Spitsbergen were sampled and analyzed to model the evolution of pore water chemistry, representing the advancement of weathering in a chronosequence. Three samples were taken at distances representing snapshots of approximately 5, 45 and 70 years of exposure. Complementary mineralogical analyses of the mineral framework and chemical analyses of pore waters, coupled with thermodynamic modelling of mineral-water interactions were applied. Recently uncovered sediments of the bottom moraine underwent very little weathering underneath the glacier cover; both the sediments and pore waters in the forefield of the Werenskioldbreen represent a very immature system. Poorly sorted sediments were deposited by the glacier and not reworked by fluvioglacial waters. The ratio of ‘amorphous iron’ to ‘free iron’ Feo/Fed increases with distance from the glacier terminus from 0.30 through 0.36 to 0.49, typical for fresh glacial till. The increase in saturation with CO2 (from p(CO2) –3.8 to –2.4) and the concentration of all major ions in pore waters (from 123 to 748 mg/L total dissolved solids, TDS) was observed in this young chronosequence. The waters evolved from carbonate- dominated to sulphate-dominated, indicating that with progress in weathering the dominating processes are equilibration with carbonates, oxidation of sulphides and the influence of gypsum precipitation by seasonal freeze-thaw cycles. Mass balance calculations and inverse modelling of the composition of pore waters, verified by microscopic observations of alteration on the surfaces of mineral grains, allowed thermodynamic confirmation of the fact that the relative significance of carbonate weathering decreases and that of sulphate increases down the chronosequence. The participation of silicate minerals in weathering is low, indicating a relatively immature stage of weathering within this particular chronosequence. It is significant that the morphology of etch pits and the formation of secondary phases apparent on mineral surfaces were identical, regardless of the distance from the glacier terminus. This might indicate that the mechanisms of particular weathering processes at the mineral-water interface are the same at the initial as well as at the more mature stages and do not change at least within ca. 70 years of exposure.
EN
Physicochemical and microbiological examinations were conducted on the meromictic Lake Starodworskie located in Olsztyn. The temperature profile revealed a characteristic, small increase in temperature at a depth between 13 and 14 m, and permanent anaerobic conditions in the deeper water layers. Accumulation of dissolved mineral substances enhanced the thermal stability of the lake waters; electrolytic conductivity values in the water deeper than 15 m oscillated within the range of 533 - 568 μS cm^-1.
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