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The mobility of aluminium in sediments was evaluated through a one-step extraction with a strong chelating agent. Single and sequential extraction procedures for the extraction of Al were applied to four sediments from a polluted ...
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The mobility of aluminium in sediments was evaluated through a one-step extraction with a strong chelating agent. Single and sequential extraction procedures for the extraction of Al were applied to four sediments from a polluted region. A single-step extraction with 0.05 mol L~(-1) ethylenediaminetetraacetic acid (EDTA) was used, and compared with a standardized SEP as reference. The Al contents extracted into Na2EDTA were in good agreement with the sequential extraction that yeilds mobile and potentially mobile portion of Al. Extracted EDTA contents make up more than 70% of the first-three-step sum of the five-step extraction procedure. Thus, Na2EDTA extraction of Al could be applied to assess aluminium mobility changes in sediments and soils.
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Exchangeable aluminium (Al_(KCI)) and CaCl_2-extractable aluminium (Al_(CaCl_2) approximately the same value in the prognosis of detrimental effect on plants. Additional, more in-depth research should show which of the two applied...
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Exchangeable aluminium (Al_(KCI)) and CaCl_2-extractable aluminium (Al_(CaCl_2) approximately the same value in the prognosis of detrimental effect on plants. Additional, more in-depth research should show which of the two applied methods of exchangeable
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The elements of various forms of iron in three profiles sampled from different parts of the Sundargarh district in Orissa, India were determined by selective extraction procedure. The mean contents of iron were extracted by variou...
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The elements of various forms of iron in three profiles sampled from different parts of the Sundargarh district in Orissa, India were determined by selective extraction procedure. The mean contents of iron were extracted by various extracting reagents and were found to be in descending order as follows: Fe-dith > Fe-oxa > Fe-pyr > Fe-EDTA Moreover, analyses of pyrophosphate, oxalate and dithionite extractable Fe showed that with increasing soil age, the crystalline iron oxides increase at the expense of the poorly crystalline forms, This trend is reflected in the ratio of Fe-oxa/Fe-dith (Fe-ratio). The Fe-dith values are higher than the Fe-oxa values in the soils indicating that a considerable fraction is present in crystalline form, The mean contents of amorphous iron, crystalline iron and the Fe-oxa/Fe-dith ratio values estimated the degree of soil development and were found to be in the following descending order: Maran > Pusaro > Hathiapathar. Correlation between different forms of iron and selected soil properties were examined.
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DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical procedures. One of the first steps, performed to remove all of the terrain covering, is data filtrati...
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DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical procedures. One of the first steps, performed to remove all of the terrain covering, is data filtration. There is a number of filtration methods and algorithms to chose from. In this paper we would like to propose a filtration method based on fuzzy logic. We present basic information regarding fuzzy logic, the design of fuzzy rules and an example of point cloud processing. For comparison, results from the ATIN filtration method are presented.
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DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical procedures. One of the first steps, performed to remove all of the terrain covering, is data filtrati...
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DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical procedures. One of the first steps, performed to remove all of the terrain covering, is data filtration. There is a number of filtration methods and algorithms to chose from. In this paper we would like to propose a filtration method based on fuzzy logic. We present basic information regarding fuzzy logic, the design of fuzzy rules and an example of point cloud processing. For comparison, results from the ATIN filtration method are presented.
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The levels of extractable aluminum (Al) in soils of tea plantations, Al concentrations in tea leaves and the impact of nitrogen fertilization on these two parameters were investigated. In addition, the properties of soils from tea...
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The levels of extractable aluminum (Al) in soils of tea plantations, Al concentrations in tea leaves and the impact of nitrogen fertilization on these two parameters were investigated. In addition, the properties of soils from tea plantations were compared to those from soils of adjacent non-tea fields to evaluate the effect of land use conversion (from non-tea soils to tea soils). Exchangeable Al (extracted in 1 mol l~(-1) KCl) ranged from 0.03 to 7.32 cmol_c kg~(-1) in 94 tea fields and decreased rapidly with increasing soil pH. In comparison with non-tea soils, tea soils had a significantly lower pH and exchangeable Mg~(2+) concentration but higher organic matter contents and exchangeable K~+ concentration. Contents of extractable Al were not different (P > 0.05) between these two soils. The concentrations of Al in mature tea leaves correlated significantly with exchangeable Al in soil samples taken at a depth of 20-40 cm and with exchangeable Al saturations in soil sampled at depths of 0-20 and 20-40 cm. In the pot experiment, nitrogen fertilization significantly increased extractable Al levels but decreased soil pH and the levels of exchangeable base cations. Nevertheless, the levels of Al in mature leaves and young shoots were significantly reduced by the application of large amounts of N fertilizer.
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This paper presents a new method of recycling aluminum and iron in boiler slag derived from plants that use coal as fuel. The new method integrates efficient extraction and reuse of the leached pellets together. An elemental analy...
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This paper presents a new method of recycling aluminum and iron in boiler slag derived from plants that use coal as fuel. The new method integrates efficient extraction and reuse of the leached pellets together. An elemental analysis of aqueous solutions leached by sulfuric acid was determined by EDTA-Na2-ZnCl2 titra-tion method. The components and microstructures of the samples were examined by means of XRF, XRD and SEM. An aluminum extraction efficiency of 86.50% was achieved when the sintered pellets were leached using 4 mol - L ' H_2SO4 at solid/ liquid [m(g)/K(mL)] ratio of 1 : 5 at 80 deg C for 24 h. An iron extraction efficiency of 94.60% was achieved in the same conditions for the maximum extraction efficiency of Al. The extraction efficiencies of Al and Fe increased with an increase in temperature, leaching time and acidity. The concentration of alumina and iron hydroxide in the final product was determined to be 99.12% and 92.20% respectively. This product of alumina would be used directly for the production of metallic aluminum.
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Objective: The EEG signal extraction offers an opportunity to improve the quality oflife in patients, which has lost to control the ability of their body, with impairment of locomotion.Electroencephalogram (EEG) signal is an impor...
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Objective: The EEG signal extraction offers an opportunity to improve the quality oflife in patients, which has lost to control the ability of their body, with impairment of locomotion.Electroencephalogram (EEG) signal is an important information source for underlying brainprocesses.Materials and Methods: The signal extraction and denoising technique obtained through timedomainwas then processed by Adaptive Line Enhancer (ALE) to extract the signal coefficient andclassify the EEG signals based on FF network. The adaptive line enhancer is used to update thecoefficient during the runtime with the help of adaptive algorithms (LMS, RLS, Kalman Filter).Results: In this work, the least mean square algorithm was employed to obtain the coefficientupdate with respect to the corresponding input signal. Finally, Mat lab and verilog HDL languageare used to simulate the signals and got the classification accuracy rate of 80%.Conclusion: Experiments show that this method can get high and accurate rate of classification. Inthis paper, it is proposed that a low-cost use of Field Programmable Gate Arrays (FPGAs) can beused to process EEG signals for extracting and denoising. As a preliminary study, this work showsthe implementation of a Neural Network, integrated with ALE for EEG signal processing. Thepreliminary tests through the proposed architecture for the activation function shows to bereasonable both in terms of precision and in processing speed.
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This paper investigates the two dimensional (2D) and three dimensional (3D) morphologies of the Fe bearing intermetallics that forms during the direct chill casting of an AA6063 Al alloy. An intermetallic phase extraction techniqu...
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This paper investigates the two dimensional (2D) and three dimensional (3D) morphologies of the Fe bearing intermetallics that forms during the direct chill casting of an AA6063 Al alloy. An intermetallic phase extraction technique was used to facilitate 3D intercon-nectivity, morphology and fraction of intermetallics. Metallographic 2D analyses suggest the presence of Chi nese-script-type and needle-type morphology Fe bearing intermetallics typically at the primary Al grain boundaries, whereas 3D analyse of the extracted intermetallics suggests those particles have dendrite-type and platelet-type mor phologies. In-addition, globular shaped intermetallics which were observed in 2D within the primary Al grains where observed to have sphere shaped rosette-type mor phology in 3D. α_c-AlFeSi and β-AlFeSi were the two dominant intermetallic phases observed in the as-cast bil let. Clusters of Ti rich particles were observed at the point from which growth appears to have started suggesting a possible nucleating site for the Fe intermetallics to form during solidification.
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This paper investigates the two dimensional (2D) and three dimensional (3D) morphologies of the Fe bearing intermetallics that forms during the direct chill casting of an AA6063 Al alloy. An intermetallic phase extraction techniqu...
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This paper investigates the two dimensional (2D) and three dimensional (3D) morphologies of the Fe bearing intermetallics that forms during the direct chill casting of an AA6063 Al alloy. An intermetallic phase extraction technique was used to facilitate 3D intercon-nectivity, morphology and fraction of intermetallics. Metallographic 2D analyses suggest the presence of Chi nese-script-type and needle-type morphology Fe bearing intermetallics typically at the primary Al grain boundaries, whereas 3D analyse of the extracted intermetallics suggests those particles have dendrite-type and platelet-type mor phologies. In-addition, globular shaped intermetallics which were observed in 2D within the primary Al grains where observed to have sphere shaped rosette-type mor phology in 3D. α_c-AlFeSi and β-AlFeSi were the two dominant intermetallic phases observed in the as-cast bil let. Clusters of Ti rich particles were observed at the point from which growth appears to have started suggesting a possible nucleating site for the Fe intermetallics to form during solidification.
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