the chemical speciation of heavy metals (arsenic, chromium, copper, lead, zinc and tin) in the sediments offormer tin mining catchment bestari jaya, peninsular malaysia was determined by using the latest version of the community bureau of reference, usually called the bcr 3-step sequential extraction procedure. furthermore, a fourth step was introduced for digestion and analysis of the residue....

introduction: this study was carried out to determine elements (li, na, k, mg, ca, ba, b, al, si, v, cr, mn, fe, co, ni, cu, zn, se, ag and p) in the suaeda vermiculata (s. vermiculata) and suaeda aegyptiaca (s. aegyptiaca) in three different regions of southern iran using inductively coupled plasma optical emission spectrometry (icp-oes) after microwave-assisted acid digestion. materials and m...

Iron oxide nanocomposites of magnetic particles coated with zirconia were used as affinity probes to selectively concentrate phosphopeptides from tryptic digests of alpha- and beta-caseins, milk, and egg white to exemplify the enrichment of phosphopeptides from complex samples. Phosphopeptides, in quantities sufficient for characterization by matrix-assisted laser desorption/ionization mass spe...

Residual metal impurities in carbon nanotubes (CNTs) provide a means to distinguish CNT from non-CNT sources of elemental carbon in environmental samples. A practical and cost-effective analytical approach is needed to support routine surface monitoring of CNT metal tracers using wipe sampling. Wipe sampling for CNT metal tracers is considered a qualitative indicator of the presence of CNTs, no...

The increasing requirements for the environmental protection have resulted in the search for more effective, inexpensive and ecologically safe solutions. Zeolite is one of the alternatives, which due to their peculiar structure are widely used for various environmental processes. The demand for an easily accessible and inexpensive source of zeolite has raised interest in synthesis of these mine...

This manuscript describes a new protocol for determination of Pa/Th/U in marine sediments. It is based on microwave-assisted digestion and represents an important reduction of working time over conventional hot-plate digestion methods, and the use of HClO(4) is avoided. Although Th and U are completely dissolved with a first microwave step, around 40% of (231)Pa remains undissolved, and a short...

This paper presents a review of methods that improve the production of volatile fatty acids (VFA) from excess sludge during the anaerobic digestion process. These methods are mainly divided into two approaches. The first approach is located in the pre-treatment methods, which change the properties of the substrates, such as thermal pre-treatment, alkaline pre-treatment, microwave pre-treatment ...

BACKGROUND Microwave is the most reliable sample digestion method. However, it requires expensive microwave digester automation and has relatively low productivity. In this study, three non-automated digestion methods, i.e. wet acid digestion using nitric acid (HNO3) and hydrogen peroxide (H2O2), wet acid digestion using HNO3, and dry washing, are compared in order to determine the best approac...