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Sorption-desorption processes of heavy metal cations were studied in soils of very differentiated properties by means of a dynamic method. The liming of brown soil originating from heavy loam caused the lowering of the desorption of heavy metal cations in the dynamic conditions.
Processes of desorption of heavy metal cations in soils of different physico-chemical properties were investigated in dynamic conditions. The liming of the sandy, loamy, and loessial soils caused the decrease of desorption degrees of Pb2+, Cu2+, and Cr3+ cations under the influence of Ba2+, Ca2+, K+, Mg2+, and NH4 Cations.
Model studies on the behaviour of Cu²⁺, Pb²⁺, and Cr³⁺ cations in soils were carried out in the conditions of forced flow. Soil samples (loess, loam and sand) were saturated with the solutions of CuCl₂, CrCl₃ and Pb(NO₃)₂ up to full sorptive saturation and then they were eliminated with exchangeable cations K⁺, NH⁺, Ba²⁺, Ca²⁺, and Mg²⁺. The effluent from soil column was analysed as to copper, lead and chromium content with atomic absorption spectrophotometry method. The soil samples used in the study varied in their reaction. Comparing the amount of Cu²⁺, Pb²⁺, and Cr³⁺ cation desorption from loess, loam and sand, it has been found that the soil liming caused the diminishing of desorption under the influence of all cations eliminating them. This diminishing was affected both by the formation of insoluble compounds in neutral reaction and their more stable binding in the soil sorption complex.
Description processes of Fe2+, Fe3+, and Mn2+ cations were investigated in three soil types characteristic for Poland, in differentiated pH and soil aeration conditions. The investigations were carried out in dynamic conditions. The soil aeration was evaluated by means of ODR and Eh coefficients. It was shown that both soil reaction and redox equilibrium in the soils and the soil surface area were the factors determining changes in the desorption of heavy metal cations from the soils sorptive complex.
This study examined the courses of sorption and of leaching with water of the heavy metal cations Ni²⁺ , Cu²⁺, Zn²⁺, and Cr³⁺ in three mineral soils (two lessive soils derived from weakly loamy sand and from loess and brown soil derived from heavy loam) under different oxygen conditions. ODR and Eh were measured as indices of soil oxygenation. It was found that soil redox equilibrium conditioned the changes of sorption magnitude of all the heavy metal cations studied.
Dynamic sorption, washing out, and desorption by Mg2+ cation of Cd2+, Cu2+ cations were investigated in 3 kinds of Polish mineral soils. The highest sorption properties under these circumstances were observed in loamy solil. Processes of desorption of heavy metal cations in dynamic conditions were caused differentatiated desorption under the influence of Mg2+ cation.
Przeprowadzono badania modelowe zakresu i przebiegu procesów sorpcyjno-desorpcyjnych kationów miedzi(II), niklu(II) i cynku podczas nasycania nimi trzech gleb mineralnych, a także wymywania wodą oraz kationem amonu w warunkach wymuszonego przepływu. Sorpcja Ni²⁺ i Cu²⁺ uzależniona była od zawartości minerałów ilastych oraz od zawartości próchnicy. Wymywanie zasorbowanych uprzednio metali ciężkich kationem amonu wykazało zróżnicowaną wielkość ich desorpcji w zależności od gatunku gleby.
The course and range of sorption and leaching with water of cations Pb²⁺, Co²⁺, and Cd²⁺ in mineral soils (sandy, loessial and loamy) were studied under different oxygen conditions. It was found that in the state of oxygen deficiency only the sandy soil responded with an increased sorptive capacity in relation to the investigated cations.
Przeprowadzono badania modelowe zakresu i przebiegu procesów sorpcyjno-desorpcyjnych kationów miedzi (II), niklu (II) i cynku podczas nasycania nimi trzech gleb mineralnych, wymywania wodą oraz kationem potasu w warunkach wymuszonego przepływu. Sorpcja badanych kationów metali ciężkich była uzależniona od powierzchni właściwej gleb. Wymycie zasorbowanych uprzednio metali ciężkich kationem potasu wykazało zróżnicowaną wielkość ich desorpcji w zależności od gatunku zastosowanej gleby.
Samples taken from level A₁ of grey-brown podzolic soil and brown soil formed from weakly loamy sand, loess and heavy loam have been tested. The studies were carried out in laboratory conditions in soils of acid and neutral reaction. Acid soil was made neutral through liming. Ions of the following metals: Fe²⁺, Mn²⁺, Ni²⁺, Cu²⁺, Co²⁺, Cd²⁺, Zn²⁺, Fe³⁺, Cr³⁺ were introduced into the samples by means of dynamic method. They all were in form of chloride solutions except Pb²⁺ which was in the form of nitrate solution. Then, metal ions not eluted with distilled water, i.e., sorbed by soil samples were desorbed by the use of 0.05 mol/dm³ solution of magnesium chloride. The content of particular metal ions was determined in the effluent by classical flame method with the use of atomic absorption spectrophotometry (AAS). It was found that the acidification of soils causes, in general, the increase of tested metal ion desorption by Mg²⁺ with the exception of Fe²⁺, Mn²⁺, and Ni²⁺ in loess soil and Fe³⁺ in sandy soil.
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