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Promocja produkcji energii z odnawialnych źródeł jest jednym z głównych celi europejskiej polityki energetycznej. Artykuł przedstawia porównanie stosowanego w Polsce i w wybranych krajach UE mechanizmu wsparcia finansowego energetyki odnawialnej. Omówione zostały dwa najczęstsze systemy promocji: mechanizm zielonych certyfikatów oraz cen gwarantowanych.
Poland’s accession to the EU has caused a necessity of harmonising Polish with the union law also in the field of energy law. It also enforces achievement of 7,5% share of energy from alternative sources in the total energy consumption in 2010. Execution of this international commitment will require more economic and legal support from the state. The development of alternative sources of energy creates chances of development of rural areas where these kinds of installations are being mostly located. This article presents an analysis of the economic efficiency of energy production on an example of 5 small hydroelectric power stations. The analysis is based on a comparison of full unit costs and unit revenue from energy sale. Bigger stations proved economically efficient while for the smaller the break even point is associated with an average water flow of 153 million m3/year.
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Economic appraisal of flood protection projects

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A model of the economic appraisal of flood protection projects using the NPV indicator is presented with a recent enlargements concerning economic valuation of casualties and psychological losses in victims’ well-being. This year’s series of big floods in Poland has made this topic come back to public attention.
 Bacteria have developed multiple complex mechanisms ensuring an adequate response to environmental changes. In this context, bacterial cell division and growth are subject to strict control to ensure metabolic balance and cell survival. A plethora of studies cast light on toxin-antitoxin (TA) systems as metabolism regulators acting in response to environmental stress conditions. Many of those studies suggest direct relations between the TA systems and the pathogenic potential or antibiotic resistance of relevant bacteria. Other studies point out that TA systems play a significant role in ensuring stability of mobile genetic material. The evolutionary origin and relations between various TA systems are still a subject of a debate. The impact of toxin-antitoxin systems on bacteria physiology prompted their application in molecular biology as tools allowing cloning of some hard-to-maintain genes, plasmid maintenance and production of recombinant proteins.
Aim of study The aim of the study was to determine the effect of deforestation of different genesis on the spatial differentiation of NO₃⁻ concentration in the Polish Tatras. Materials and methods In 2018, 728 water samples were collected in the Tatras by hydrological and chemical survey. In the Hydrological and Chemical Laboratory of IGiGP UJ, ion chromatography determined: Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃⁻, SO₄²⁻, Cl⁻, NO₃⁻, NO²⁻, NH₄⁺, PO₄³⁻, Li⁺, F⁻ and Br⁻. Nitrates from 1719 water samples were analyzed in order to compare their current concentration to the period of 2007–09 (n = 991 water samples). The Tatras were divided into 13 areas. Results and conclusions The chemical composition of waters draining both forested and deforested Tatra slopes showed that in the decade from 2007–09 to 2018 the concentrations of NO₃ increased rapidly. In 2018, an average NO₃⁻ concentration expressed by median was higher by as much as 60.2%, rising from 1.76 to 2.82 mg · dm⁻³. The fluctuations in maximum concentrations were more pronounced, because their multiple increase occurred in five valleys, with the largest in: The Lejowa (by 348.2%) from 4.75 to 21.30 mg · dm⁻³; over double: Małej Łąki, Za Bramką and in Suchy Żleb; Kościeliska with Staników Żleb; Strążyska, Ku Dziurze and Spadowiec and Olczyska. Only in two areas the concentrations were lower. Comparison of the average NO₃⁻ concentration in Tatra waters has definitely proven its higher levels than in other regions of Poland in forested catchments or agricultural catchments, with the exception of catchments with intensive agricultural activities. Diverse genesis of deforestation result in strong mosaic–like spatial differentiation of the NO₃⁻ concentration. In waters draining the slopes deforested due to windfall, there is a concentration of NO₃⁻ > 10 mg · dm⁻³, which can potentially cause an unfavorable phenomenon of eutrophication of waters, however, it has a natural cause.
Bark beetle outbreaks and tree mortality patterns should be better understood to control outbreak impacts. We investigated landscape-level patterns of Norway spruce mortality caused by Ips typographus outbreaks across three periods from 1999–2012 in Tatra National Park (Poland) using high-resolution aerial orthophotos and satellite imagery. Shifts in tree mortality related to elevation, slope, and solar equinox radiation were analyzed with ANOVAs (Tukey's HSD tests). Boosted regression trees were employed to assess the forecasting effectiveness of these variables related to mortality period. Spruce mortality severity increased significantly across time in both managed and unmanaged forests. Management activities did not effectively reduce spruce mortality severity. Mortality severity increased significantly at higher elevations over time, while slope and radiation trends varied. Elevation and radiation were the best forecasters of mortality period, exhibiting moderate predictive ability. Beetle-induced spruce mortality increased significantly in Tatra National Park from 1999–2012, particularly at high elevations. Management strategies aimed at minimizing spruce mortality have been ineffective.
Tuganowski, W., Korczyńska, I., Wąsik, K., Wójcik В. and Bukowski, M.; Effects of forskolin on the longitudinal internal resistance (ri) in rabbit sinus node strips. Aclta physiol. pod., 1989, 40 (2): 164-170. The effect of several concentrations of 7-0-hemisucoinyl, 7-deacetyl forskolin on n was studied by means of microelectrode and single sucrose gap techniques. Twenity µmol·1⁻¹ of forskolin added ifco to the sucrose gap lowered ri 15% below the control value. The drug applied at 50 µmol·l⁻¹ initially decreased ri by 31%, and then it increased the resistance by 43% above the control, value. The possible mechanisms underlying these effects are discussed in terms of cAMP and Ca action on the cell coupling.
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