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The samples were taken from 7 profiles of alluvial soils formed from varied gytias on calcareous sinter. The research concerned determination of composition of exchangeable cations and basic saturation. In the analysed soils, lithologic discontinuities in the profile structure were observed. The calcareous sinter located in the lower part of the profile caused characteristic water properties and occurrence of gleyic process. The investigated soil profiles were varied in their morphological structure and physicochemical properties. Fluctuations in the content of carbonates, organic mater and non-carbonate mineral substance confirmed the existence of several cycles in the formation of these soils. The basic saturation (S) of the analysed soils ranged between 287.4 and 2238.7 mmol(+) kg–1. The highest values were detected in gytia horizons (gyd), and the lowest ones - in gleyic horizons (G). The dominant cation in sorption complex of all horizons was calcium, and its highly differentiated content ranged from 245.3 to 2089.6 mmol(+) kg–1. Magnesium was the second most abundant cation in sorption complex. The content of Mg2+ ranged from 19.4 mmol(+) kg–1 in clay-lime gytia horizons to 143.5 mmol(+) kg–1 in lime gytia horizons. The lowest in the content among exchangeable cations in the analysed samples was potassium (0.6-12.9 mmol(+) kg–1). Our comparison of the divalent cation content (Ca2+, Mg2+) and monovalent cation content (Na+, K+) showed significant instability of the balance between these groups of cations, which was confirmed by a very wide range of the ratio (21.3-333.1) calculated between these two groups of cations. The amount of alkaline cations in the analysed soilsfollowed this order: Ca2+ > Mg 2+ > Na+ > K+ .
The effect of divalent cations in concentrations 10-9-10-3M upon the hemolysis of sheep erythrocytes induced by resorcinolic lipids was studied. It was demonstrated that the process of hemolysis is inhibited by divalent cations present in the incubation medium. The extent of inhibition is dependent on both type of the cation and hemolytic agent. In alkylresorcinol-induced hemolysis the most effective in protection of the cells were Zn2+ and Co2+ cations. Weaker protective action was observed for Cd2+ and Mn2+. Calcium ions, in all studied concentrations, were without marked effect on the level of relative hemolysis. Magnesium ions as well as Ba2+ in nanomolar concentrations were effective inhibitors of the lysis but this effect diminished at higher (millimolar) concentrations of these ions. When alkenylresorcinols were used as hemolysis-inducers no effective protection of erythrocytes by Ca2+, Ba2+ or Mg2+ was observed. Most effective in protection of cells against this amphiphile-induced lysis, similarly to their effect observed previously for various lytic agents, were cations of Zn2+, Co2+ and Cd2+. Mn2+ cations were intermediate, with respect to their protective potency.
Chemical nature, thermodynamic and kinetic properties of metal cations in aqueous solutions are de­scribed and discussed in terms of structural factors controlling physical properties of the systems. The structure of hydrated cations, reaction mechanism of water exchange on the cations, hydrolytic phenomena and acidity of the cations are presented. Correlations between coordination states of the salts in and bulk properties of the solutions are indicated. Elements of aquatic chemistry are presented.
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.
This report presents an assessment of pyrite weathering on the chemistry of water in the abandoned Podwiśniówka quarry of the Holy Cross Mountains (south-central Poland). This quarry did not operate for ore minerals, but for quartzites. The area of the pit pond enlarges each year generally as a result of an influx of spring snowmelt or heavy rainfall. The water examined reveals a very low pH, varying from 2.27 to 3.57 (with geometric mean value of 2.90), and unusual low concentrations of cations and anions, especially total Fe (2.7–24.0 mg·L⁻¹) and SO₄²⁻ (55–285 mg·L⁻¹). With regard to its chemistry, this pond is unique compared to similar sites in Poland and even throughout the world. The low pH and element concentrations are attributed to the specific mineralogy of ore and gangue minerals, as well as complex bacterially catalyzed geochemical processes that have encompassed pyrite oxidation and iron oxidation/hydrolysis reactions.
The sorption behaviour of divalent cations M+ (Cu, Pb and Zn) and trivalent cations M3+ (Fe, Al) with humic acid isolated from oxidized coal (Hazro,SE Anatolia,Turkey) was followed in aqueous solution. Coal humic acid and metal ion interaction was investigated with special emphasis on the effects of pH, metal ion concentration and humic acid concentration. It has been found that the interaction of humic acid with metal ions in solution increases with pH, decreases with metal ion concentration and increases with humic acid concentration. The differences in sorption ability of particular metal ions on oxidized coal-derived humic acid are Fe> Pb> Cu> Al> Zn and Fe> Pb> Al> Cu> Zn at pH 2.5 and 3.5, respectively, while they are Fe=Pb=Cu=Al> Zn at both pH 4.5 and 5.5. The interaction of some trivalent (Fe, Al) and divalent(Cu, Pb, Zn) metal ions with humic acid prepared from coal was also studied using FTiR spectroscopy. This has proven helpful with respect to metal binding to understand better the potential sites of binding within the humic acid. Infrared spectroscopy showed the participation of cOOH and OH groups in binding to the metal ions.
The aim of the study was to determine the effect of competition between heavy metal cations on sorption extent of Cu2+ and Co2+ as well as to estimate of their mobility in soils through desorption with 0.05 M CaCl2 solution. The one-component CuCl2 or CoCl2, two-component CuCl2 and CoCl2 or three-component CuCl2, CoCl2 and Pb(NO3)2, CrCl3, NiCl2, ZnCl2 or CdCl2 solutions were introduced into the columns with two grey-brown podzolic soils. Cations of Cu2+ affected non-specific and specific Co2+ sorption extent while Co2+ had a smaller effect on Cu2+ sorption. In the three-component systems Cu2+ and Co2+ sorption was mostly inhibited by Pb2+ and Cr3+ but only to a small extent by cations of other heavy metals under investigation.
Research was carried out on the basis of investigations from the years 1996-1998 on the so-called monoliths in the soils derived from loess formations. Properties of those formations were differentiated by landscape and processes of water erosion. It was found out that post-sewage waters (waters received after sewage treatment) from a mechanical-biological sewage treatment plant have a more favourable influence on both the value of acidification indexes and relations between cations in the soils than solid mineral salts.
W pracy przedstawiono wyniki badań zawartości wybranych kationów i anionów w wodach mineralnych, dostępnych w województwie mazowieckim. Uzyskane wyniki porównano z danymi deklarowanymi przez producentów tych wód. Badaniu poddano wody: Bonaqua, Cisowianka, Mazowszanka, Krynica Zdrój, Arctic, Czantoria, Naturalna woda mineralna Lider Price i Żywiecki Kryształ.
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