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Ostrava, Czech Republic

Durability and aesthetical characteristics of wooden products exposed outdoor are influenced by various factors: – wood species, treatment of wood, severity of exposure, etc. In this study have been investigated effects of accelerated weathering (in Xenotest with alternation of UV-light irradiation and water spray) on colour changes of samples from selected wood species (Scots pine − Pinus sylvestris L., beech − Fagus sylvatica L., and Norway spruce − Picea abies Karst. L.) painted with 1, 2 or 3 layers of brown acrylic coating Superwax. The lowest colour stability, valued in the CIE-L*a*b* colour system, had surfaces of beech wood painted only with 1 layer of Superwax. On the other hand, the highest resistance against discoloration had the spruce wood painted with 3 layers of this coating. © 2015, Technical University in Zvolen. All rights reserved.

Miroslav K.Y.N.C.L.,Technicka Univerzita Ostrava
Carpathian Journal of Earth and Environmental Sciences | Year: 2014

Samples of water and sludge were analysed from two different water treatment plants which produce drinking water from surface sources taken in two territories with different geology. In one territory, polymetalic deposits of Cu, Pb, Zn are located (primary rocks - Kulm). The second territory is located in the flysch range with no presence of heavy metals. Concentration of heavy metals (Cu, Cr, Ni, Pb, Cd, As, Hg, B) in water was below detection limits. Analyses of the sludge produced during coagulation filtering treatment have proved presence of heavy metals in the sludge. Following metals in the sludge: As, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Zn. Most heavy metals are of anthropogenic origin. It is only Zn and As which originate in the geology of the catchment area. The heavy metal concentrations were low, the exception being As which was 30.6 mg/kg in dry mass of sludge for the Podhradí water treatment plant. This value is three times higher than the limit permitted for the sludge. Regular monitoring of heavy metal concentration in the water treatment sludge will improve assessment of presence of the heavy metals in the treated water.

Vrtek M.,Technicka Univerzita Ostrava
Proceedings of the 11th International Scientific Conference Electric Power Engineering 2010, EPE 2010 | Year: 2010

The present paper deals with the evaluation of the effectiveness of basic types of heat pumps. The coefficient of performance (COP) is solved from various viewpoints. In the fist case there is the COP solved from the direct energy input. In the second case the direct energy input is resolved to exergy. Finally, the recalculation to primary energy was done. All of these methods are useful for evaluation but each of them has its specific application. There are performed comparisons of compressor electric-driven and combustion engine-driven heat pumps and absorption heat pumps.

IEC 61000-4-15 (Functional and design specification of flickermeter) specifies normalized flicker response and manufacturers must fit in with performance testing. Experience has shown that flickermeter implementations from different manufacturers, that process rectangular modulation patterns in identical manners, may still deviate from each other when processing other non-uniform voltage fluctuations. The paper describes generation of reproducible voltage varying signals with envelope shape typical for sawmill, heat pump, granulator, then it describes the unit under test and comparison of results.

Mruzek M.,Neurochirurgicka klinika FN | Litschmannova M.,Technicka Univerzita Ostrava | Palecek T.,Neurochirurgicka klinika FN | Lipina R.,Neurochirurgicka klinika FN
Prakticky Lekar | Year: 2016

The authors evaluated effect of vertebroplasty and vertebral body stenting in treatment of osteoporotic vertebral fractures, in three years follow up. In both groups ODI and VAS score were evaluated, and height of vertebra was measured after the operation. In both groups ODI and VAS values decreased, and a statistically significant difference in values in favour stentoplasty was found. In both groups, there was an increase in the height of the vertebral body in the front and middle parts, in the three-year period there was a statistically significant difference in keeping the height of the vertebral body in favour of stentoplasty. Authors evaluate the both methods as effective in the treatment of osteoporotic vertebral fractures. In terms of pain reduction and vertebral body reposition, stentoplasty is considered as more beneficial. The authors evaluate both methods as safe, minimal number of complications was recorded.

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