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Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction. Fractionation of plutonium isotopes Pu, ,Pu in environmental samples i. Mercury and trace element fractionation in Almaden soils by application of different sequential extraction procedures. Sanchez, D. A comparative evaluation of the mercury distribution in a soil sample from Almaden Spain has been performed by applying three different sequential extraction procedures, namely, modified BCR three steps in sequenceDi Giulio-Ryan four steps in sequenceand a specific SEP developed at CIEMAT six steps in sequence.
There were important differences Chatroulette adult gambonewfoundland the mercury extraction obtained by the three procedures according to the reagents applied and the sequence of their application. These findings highlight the difficulty of setting a universal SEP to obtain information on metal fractions of different mobility for any soil sample, as well as the requirement for knowledge about the mineralogical and chemical characteristics of the samples. The distribution of mercury and major, minor, and trace elements in the different fractions were determined.
The indicate that mercury is mainly released with 6 M HCl. Minor mercury is found in the fraction ased to oxidizable matter and in the final insoluble residue cinnabar. Pumpkin Cucurbita maxima seed proteins: sequential extraction processing and fraction characterization. Seed proteins extracted from Tunisian pumpkin seeds Cucurbita maxima were investigated for their solubility properties and sequentially extracted according to the Osborne procedure. The solubility of pumpkin proteins from seed flour was greatly influenced by pH changes and ionic strength, with higher values in the alkaline pH regions.
It also depends on the seed defatting solvent. On the basis of differential solubility fractionation and depending on the defatting method, the alkali extract AE was the major fraction The denaturation temperatures were Pumpkin protein extracts with unique protein profiles and higher denaturation temperatures could impart novel characteristics when used as food ingredients.
Element fractionation by sequential extraction in a soil with high carbonate content. The influence of carbonate and other buffering substances in soils on the of a 3-step sequential extraction procedure BCR used for metal fractionation was investigated. Deviating from the original extraction scheme, where the extracts are analysed only for a limited of metals, almost all elements in the soils were quantified by X-ray fluorescence spectroscopy, in the initial samples as well as in the residues of all extraction steps. Additionally, the mineral contents were determined by X-ray diffractometry.
Using this methodology, it was possible to correlate changes in soil composition caused by the extraction procedure with the release of elements. Furthermore, the pH values of all extracts were monitored, and certain extraction steps were repeated until no ificant pH-rise occurred. Applying the original BCR-sequence to the calcareous soil, carbonate was found in the residues of the first two steps and extract pH-values rose by around two units in the first and second step, caused mainly by carbonate dissolution. This led to wrong asment of the carbonate elements Ca, Mg, Sr, Ba, and also to decreased desorption and increased re-orption of ions in those steps.
After repetition of the acetic acid step until extract pH remained low, the carbonate was completely destroyed and the distributions of the elements Ca, Mg, Sr, Ba as well as those of Co, Ni, Cu, Zn and Pb were found to be quite different to those determined in the original extraction. Furthermore, it could be shown that the effectiveness of the reduction process in step two was reduced by increasing pH: Fe oxides were not ificantly attacked by the repeated acetic acid treatments, but a fold amount of Fe was mobilized by hydroxylamine hydrochloride after complete carbonate destruction.
On the other hand, only small amounts of Fe were released anyway. Even repeated reduction steps did not. Fractionation study in bioleached metallurgy wastes using six-step sequential extraction. The stored metallurgy wastes contain residues from ore processing operations that are Chatroulette adult gambonewfoundland by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria.
In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland Szklary. Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied.
To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.
Comparison of three sequential extraction procedures to describe metal fractionation in anaerobic granular sludges. In the last few decades. In this study. Tessier, P. Campbell, M. Bisson, Anal. Metal fractionation of atmospheric aerosols via sequential chemical extraction : a review. This review surveys schemes used to sequentially chemically fractionate metals and metalloids present in airborne particulate matter. It focuses mainly on sequential chemical fractionation schemes published over the last 15 years.
These schemes have been classified into five main : 1 based on Tessier's procedure, 2 based on Chester's procedure, 3 based on Zatka's procedure, 4 based on BCR procedure, and 5 other procedures. The operational characteristics as well as the state of the art in metal fractionation of airborne particulate matter, fly ashes and workroom aerosols, in terms of applications, optimizations and innovations, are also described.
Many references to other works in this area are provided. Assessment of the BCR sequential extraction procedure Chatroulette adult gambonewfoundland thallium fractionation using synthetic mineral mixtures. Fractionation of potentially toxic elements in urban soils from five European cities by means of a harmonised sequential extraction procedure. Davidson, Christine M. The revised four-step BCR sequential extraction procedure has been applied to fractionate the chromium, copper, iron, manganese, nickel, lead and zinc contents in urban soil samples from public-access areas in five European cities.
A preliminary inter-laboratory comparison was conducted and showed that data obtained by different laboratories participating in the study were sufficiently harmonious for comparisons to be made between cities and land types e. Iron, nickel and, at most sites, chromium were found mainly in association with the residual phase of the soil matrix.
Copper was present in the reducible, oxidisable and residual fractionswhilst zinc Chatroulette adult gambonewfoundland found Chatroulette adult gambonewfoundland all four sequential extracts. Manganese was strongly associated with reducible material as, in some cities, was lead. As would be expected, extractable metal contents were generally highest in older, more heavily industrialised cities. Copper, lead and zinc showed marked and often correlated variations in concentrations between sites within the same city whereas manganese and, Chatroulette adult gambonewfoundland, iron, did not.
No overall relationships were, however, found between analyte concentrations and land use, nor between analyte partitioning and land use. Physico-chemical and viscoelastic properties of high pressure homogenized lemon peel fiber fraction suspensions obtained after sequential pectin extraction.
Willemsen, K. The viscoelastic properties of high pressure homogenized lemon peel cell wall fiber suspensions, obtained after sequential selective pectin extractionwere investigated in the current study. For comparison, a general pectin extraction was additionally performed on lemon peel under acid thermal. Fractionation of metals by sequential extraction procedures BCR and Tessier in soil exposed to fire of wide temperature range. Forest fire presents serious problem, especially in Mediterranean Region.
Effects of fire are numerous, from climate change and deforestation to loss of soil organic matter and changes in soil properties. To evaluate the influence of organic matter on Chatroulette adult gambonewfoundland under fire, three soil samples were analysed and compared: a the one with added coniferous organic matter; b deciduous organic matter b and c soil without additional organic matter.
Type of organic matter is closely related to pH of soil, as pH is influencing the mobility of some pollutants, e. For that reason pH was also measured through all experimental steps. After heating, whereby fire effect on soil was simulated, samples were analysed by BCR protocol with the addition of a first step of sequential extraction procedure by Tessier and analysis of residual by aqua regia.
Selected metal concentrations were determined using inductively coupled plasma atomic emission spectrometer. Further on, loss of organic matter was calculated after each heating procedure as well as the mineral composition. The mineral composition was determined using an X-ray diffraction. From obtainedit can be concluded that temperature has an influence on concentration of elements in specific step of. Occurrence and abundance of carbohydrates and amino compounds in sequentially extracted labile soil organic matter fractions.
This study aimed to investigate the content of carbohydrates and amino compounds in three labile fraction of soil organic matter SOM. On-line dynamic fractionation and automatic determination of inorganic phosphorous in environmental solid substrates exploiting sequential injection microcolumn extraction and flow injection analysi.
Sequential injection microcolumn extraction SI-MCE based on the implementation of a soil containing microcartridge as external reactor in a sequential injection network is, for the first time, proposed for dynamic fractionation of macronutrients in environmental solids, as exemplified by the pa Sequential injection microcolumn extraction SI-MCE based on the implementation of a soil containing microcartridge as external reactor in a sequential injection network is, for the first time, proposed for dynamic fractionation of macronutrients in environmental solids, as exemplified The on-line fractionation method capitalises on the accurate metering and sequential exposure of the various extractants to the solid sample by application of programmable flow as precisely coordinated by a syringe pump.
Three different soil phase Zinc fractionation in contaminated soils by sequential and single extractions : influence of soil properties and zinc content. The soils had developed from different geologic materials and covered a wide range in soil pH 4. Input of aqueous Zn with runoff water from electricity towers during 26 to 74 yr resulted in total soil Zn contents of 3. The extractability of Zn increased with increasing Zn contamination of the soils.
In conclusion, the extractability of Zn from soils contaminated with aqueous Zn after decades of aging under field conditions systematically varied with soil pH and Zn content. The same trends are expected to apply to aqueous Zn released from decomposing Zn-bearing contaminants, such as sewage sludge or smelter slag.
The systematic trends in Zn fractionation with varying soil pH and Zn content indicate the paramount effect of these two factors on molecular scale Zn speciation. Further research is required to characterize the link between the fractionation and speciation of Zn and to determine how Zn loading and soil physicochemical properties affect Zn speciation in soils. Arsenic fractionation in agricultural soil using an automated three-step sequential extraction method coupled to hydride generation-atomic fluorescence spectrometry.
Rosas-Castor, J. Valldemossa km 7. Critical parameters that affect the performance of the automated system were optimized by exploiting a multivariate approach using a Doehlert de.Chatroulette adult gambonewfoundland
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