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Aura
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1995
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nr 12
6-7
Aluminium and aluminium alloys contained in waste affect human health. Acid rain leaches waste and introduces aluminium ions to rivers and ground water. Studies show a correlation between Alzheimer’s Disease and aluminium content in drinking water. Problems in disposing aluminium waste affect the construction (sheet metal, profiles), electrical (wires) and transport (construction of cars and airplanes) sectors. Technologies enabling re-melting of automobiles after they are used are an innovation in the automobile industry. However, such recycling results in considerable losses due to oxidation, which contribute to increased energy and labour costs. The author deals with a new technology based on direct conversion of metal waste into solid material, without melting.
Research on aluminium speciation was performed using a slightly modified version of Tessier’s procedure. The soils under study displayed strongly acidic character (pH KCl of 3.3 - 4.4). The content of aluminium in the exchangeable (11 mg/kg), acid extractable (67 mg/kg), oxidizable (2650 mg/kg), reducible (658 mg/kg) and residual fraction (24,680 mg/kg) varied widely. The percentage of labile phase (sum minus residual) obtained for mean values in the profile amounted to 12.1%, which may indicate its considerable bioavailability. The soil profile under study displayed a lithogenically dichotomous structure, which was also reflected in the aluminium content in the particular fractions.
A laboratory simulation of acid rain was performed in which soil monoliths from the Wielkopolski National Park area were sprinkled with water solutions of sulphuric acid of pH 3.0 or 2.0, and for reference with distilled water of pH 5.6. The form and amount of the washed out aluminium as well as changes in the chemical properties of the soil studied were determined. The process of aluminium release proved particularly dangerous for acidic or slightly acidic soils which cover a large part of the National Park area.
Our paper is a review of published results of tsunami deposit chemical studies. These sediments were deposited by the 26 Dec. 2004 tsunami in southern Thailand. All research was carried out by teams of geologists, chemists, and biologists from Adam Mickiewicz University, Poznań.
Our study presents the results of determining labile aluminium form in samples from the 2004 tsunamiaffected coastal zone of Thailand. The samples were collected from tsunami deposits, beach sediments, sediments underlying the tsunami deposits (pre 2004 tsunami soil), as well as from soils from areas, that were not flooded. The extraction of the labile form of aluminium was performed using 3 mol L⁻¹ HCl in twelve grain size fractions. In the surface layer samples the highest concentrations were determined in the tsunami deposits in fractions <0.063 mm (5850 mg kg⁻¹). The highest determined concentration in the whole set of investigated samples occurred in soil sample in fractions 0.09-0.125 mm (19770 mg kg⁻¹). An increase in concentration of labile aluminium form, along with decreasing grain diameter, was observed in samples from all the studied settings. In general, concentrations were higher in soil samples not affected by the tsunami. This is probably due to steady weathering of minerals during soil forming processes and removal of sediment grain surface coatings potentially enriched in labile Al during high energy transport by tsunami.
The aim of the research was to analyse the impact of soil water potential on the concentration of aluminium and selected mineral nutrients in soil solution. Soil acidification is a natural process accelerated by agriculture, and one of the most important factors limiting crop production worldwide. Concentrations of aluminium and selected mineral nutrients in solutions obtained from soil at initial pH 4.2 and after liming at various soil water potential were measured in centrifuged soil solution. Our results showed a significant gradual increase in the concentration of Al and most of mineral nutrients (Ca, Mg and P) with decreasing soil water potential from −3.5 kPa to −0.205 MPa. The results are important in the evaluation and interpretation of plant response to aluminium toxicity when accompanied by changes in water availability.
The aim of the present study was to determine the influence of the reaction and organic substance on the effectiveness of zinc and cadmium binding by Al₁₃ The presence of organic substance in the combinations with Al₁₃ and toxic elements did not block the binding Al₁₃ activity. However, its type and amount influenced the effects of cadmium and zinc immobilisation and mobilisation. Cadmium in the solution was antagonistically related to zinc and other microelements in the plant which was confirmed in the mineral composition and presentation of the studied plants.
Opakowanie
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2001
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tom 46
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nr 03
18-20
Puszki napojowe są opakowaniami jednorazowego użycia, ale aluminium, z którego są wykonane może być ponownie wykorzystane po ich zużyciu, nie tracąc przy tym nic ze swoich własności. Recykling puszek aluminiowych umożliwia zmniejszenie o 95% zużycia energii, potrzebnej do uzyskania aluminium z boksytu, a także obniżenie o 97% zużycia wody i znaczne ograniczenie skażenia powietrza.
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