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The aim of the study is the analysis of the property status of Hungarian agricultural enterprises, including main financial processes. The study is based on the corporation tax returns database collected by the NAV (National Taxation and Customs Organization) for the period 2002-2011. Referring to literature related to the topic, the study presents special features of agriculture and their effects on agricultural revenues. Invested (fixed) assets as well as current assets, including parameters describing their structures, within the scope of the financial position of enterprises, have been analysed. The description of the financial position has been conducted using the method of liquidity analysis, after which resource allocation, strictly connected with it, has been analysed.
To investigate the bioavailability and bio-enrichment of metals from soils to vegetables, the concentrationsof Ni, Pb, Zn, and Cu in vegetables and their grown soils sampled from eight suburban areas of Nanjing, China, were determined, and the fractions of these metals in soils was characterized by using the BCR sequential extraction procedure. The results showed that the residual fraction was the dominant proportion for Pb (46%-64% in total), Cu (49%-73% in total) and Ni (40%-61% in total) in soils, whereas Zn was found mainly in the oxidizable fraction (31%-69% in total). The translocation coefficients of metals in leaf/root systems revealed that Cu, Zn and Ni were mainly accumulated in roots, whereas Pb mainly in the leaves of these vegetables. The enrichment coefficients of metals in leaf/root systems indicated that Zn had the strongest capacity of accumulation from soils to vegetables among all four elements. No significant correlations were found among metal concentrations in the vegetables, the metal fractions in corresponding soils, and the enrichment coefficients from soils to plants.
This paper reports results of studies on the effects of interaction between heavy metal ions (Hg2+, Cd2+, Ni2+ and Cu2+) on the degree of desulfurication taking place using Desulfotomaculum ruminis bacteria. It has been found that mutual interaction of heavy metal ions can bring either antagonistic or synergetic effects. For instance, the toxic effect of Hg2ł ions on the process of desulfurication is minimized after the introduction of Cd2+ ions (antagonism). In other cases interaction of the metal ions studied has led to synergetic inhibition. The concentration ranges of metal ions in which they show the inhibiting effect or act as antagonists have been determined.
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The transformations of ¹⁴C-ring-labeled carbofuran and leaching with water in the humus soil were investigated. The experiments were carried out under laboratory conditions using natural profile of arable layer (mini-lysimeters) and in field lysimeter. The tested compound applied on the soil surface was eluted with water in laboratory and sprinkled four-times every 2 weeks in field trial. Carbofuran was mobile in the soil with permeable water. lts residues could reach the ground water as a result of leaching with heavy rains. The both processes, disappearance of extractable residues and formation of bound ones were most intensive in the upper layers of the soil. The using of natural soil profiles (mini-lysimeters) offer an excellent experimental set up for study of crop protection chemicals behaviour in the soil.
The extensive investigations of total and mobile heavy metals concentrations in sus­pended matter (SPM) and bottom sediments of the upper and middle Odra river were carried out over the years 1997–2000. Significant levels of contamination were found. Median concentrations for Cd, Pb, Cu, Zn and As in the SPM and sediments were (mg/kg) 7.3 and 8.9, 97.2 and 119, 79.2 and 92.7, 1221 and 1158, and 52.9 and 67.9, respectively. The highest metal pollution of Odra river solids was found with cadmium, zinc, lead and arsenic. The frequency distribution of Cd, Zn, Pb and As in both type of samples, i.e. SPM and sediments, shows high similarity. >From all metals studied, Cd, Zn and As appear to be of particular concern because of the high levels, that appear to be bio­available, and their high mobility. The exchangeable and carbonatic fractions of Cd and Zn reached up to 50% of their total amount. Besides the determination of total metal concentration, the “mobilisation test” of metals in river solids is rec­ommend for monitoring purposes, allowing evaluation of the most mobile, and bioavailable metal fractions. The results of four years of very wide studies of Odra river system suggest that for river monitoring pur­poses, the fre­quency and numbers of samples for chemical analysis of both water and solids - preferably suspended matter - could be reduced to twice a year, with few select sampling sites.
Taking advantage of the long term field stationary experiments in Skierniewice started at 1922 based on fixed mono-fertilization, the mobility of the exchangeable cations Ca, Mg, K, Na was studied for the whole soil profile up at a depth of 100 cm. Mobility was studied using an electrodialysis method to remove and determine cations in the cathode solutions. Calcium proved to be most mobile element and sodium the least mobile and the mobility ranking of exchangeable cations in the soil under investigation is as: Ca > K > Mg > Na. The genetic horizons of the soils showed differentiated mobility for individual cations. Cations in the surface horizons (up to 50 cm) are more mobile than in the deeper horizons with trace amounts of humus.
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