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Long-term hydroecological monitoring in the Krkonoše Mts
Tesař, Miroslav ; Šír, Miloslav
The cloud and fog water deposition proved to be important delivery mechanism for both water and pollutants in mountainous headwater regions. A fogwater study has been conducted in the Krkonoše Mts. since 1999 till the present time. The sampling site for the observation and evaluation occult precipitation in the Western region was established in the Modrý potok basin (1010–1554 m a.s.l., 2.62 km2) at the highest point of the watershed (passive cloud and fog water collector) while the bulk precipitation and throughfall samplers were installed near to the closure profile of the basin. Rain gauges are evenly situated at six altitudes of the watershed (from 1020 to 1365 m a. s. l.). In the Eastern region the both passive and active collectors were installed close to the Labská bouda chalet (1325 m a.s.l). The active collector (Eigenbrodt, Germany) is operated automatically by the PWD-11 sensor (Vaisala, Finland). Collected samples were stored in polyethylene bottles and transported as soon as possible to the laboratories of the Czech Geological Survey and Geological Institute of ASCR to the chemical analyses. The results for 1999–2011 will be presented in this article. A wide range of concentrations were encountered, most typically exceeding concentrations occurring in rain (so-called enrichment factors were evaluated) and the estimated wet deposition of the most important chemical compounds were calculated and compared with respect to weighted means of bulk precipitation collected in the open area. Based on the model predictions and on the water balance of the forest canopy the annual occult precipitation total for the Krkonoše Mts. was estimated by 20–25 % of the annual falling precipitation total. The research is supported by the Czech Science Foundation (205/09/1918).
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Photocatalytic aktivity of plasma treated titanium precursors
Brožek, Vlastimil ; Matějíček, Jiří ; Šrank, Z. ; Mastný, L. ; Janča, J.
Photoactive solid parts of chemical reactors could be produced via plasma deposition of boron carbide and titanium diboride using water-stabilized plasma torch WSP. Photocatalytic effectivity of TiC and TiB2 was measured, as well as those of their oxidation products gained at 450 and 1000°C on air as well as at 450°C in oxygen plasma. Photocatalytic effectivity of all studied substances was compared with those of plasma- treated TiO2 and Ti2O3, whose photocatalytic activity is known from plenty of practical applications.
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Sukcese hmyzenek (Protura) a vidličnatek (Diplura) na haldách chemické továrny
Rusek, Josef
Primary succession of Protura and Diplura was studied on deposits of a former chemical factory at Petrovice u Karviné, NE Moravia, Czech Republic, in 1978-1979, 1993 and in 2002-2004. Chemically loaded deposits were 15, 25 and 60 years old in 1979 and a primary succession without plant re-cultivation took place there. The succession was delayed on small humps and slopes where the deposited substrate was covered by terrestrial algae, lichens and mosses. Protura did not enter the primary succession before a moss cover occurred on the 15 years old heap and they were represented only by .i.Acerentulus traegardhi./i.. Three species of Protura were established in the 20 years old grass-covered stage as well as on the 49 years old heap. They occurred in low densities up to the 74 years old stage (and older), in which a proturan community of 4-6 species was established.
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Deposition methods of thin films using low-temperature plasma
GÜNZEL, Martin
This thesis is focused on the description of selected deposition methods of thin films using low-temperature plasma. Currently, many various technologies of thin films are developed and there are many applications in various industrial sectors. This thesis first gives a brief overview of deposition methods, plasma behavior during deposition and subsequent description of the selected methods of application due to the physical and chemical processes. They also discussed the advantages and disadvantages of the described coating technologies, and several examples of their use. The thesis should thus contribute to the overall view of modern coating technologies, their development and use currently, or possible use in the future.
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Flow, chemical and isotopic composition of water in unsaturated zone of the castellated sandstone at Klokočské skály area
Mikuš, Petr ; Bruthans, Jiří (advisor) ; Jiráková, Hana (referee)
The study is focused on character of flow, permeability, mean residence of water, chemical composition of water and chemical fluxes in unsaturated zone of castellated sandstone at Klokočské Skály area. Soil water as well as the water seeping from up to 15 m thick sandstone unsaturated zone consists of mixture of: A) Component with mean residence time 2-4 months (50-75% of mixture) and B) Component with mean residence time exceeding 4 years (25-50% of mixture). In winter the component A is missing in K3 drip place probably because of freezing conditions, which prevent infiltration of the fast component. Sulfates are the most abundant anion in studied waters with chemical flux in sandstone unsaturated zone (SUZ) 7-10 g/m2/year, which exceeds several times the influx from total (wet and dry) atmospheric deposition (1.2 g/m2/year). On the other hand nitrates flux is decreasing with depth (atmospheric deposition 1.7 g/m2/year; flux in SUZ 0.2-0.4 g/m2/year). Aluminum is the most abundant cation in SUZ (average concentration 6.3 mg/l, max. 35 mg/l). Flux of aluminum in SUZ is 2.5 g/m2/year, which is 80 times more that atmospheric deposition. Surprisingly the forest vegetation does not seem to suffer any directly visible damage. Silica is another substance which is intensively leached from SUZ. The most prominent...
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