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....

knowledge of the probable origin and behaviour of arsenic certainly gives valuable insights into the potential for transfer in the environment and of the risks involved in mining sites. sequential extraction analyses are common experiments often used to study the origin and behaviour of potentially toxic elements. the method, however, presents some deficiencies, including labor-intensive proced...

The determination of serum copper is of value in a number of metabolic studies, particularly in the investigation of the anemia of chronic infection. Presented here, together with illustrative data, is a method for determining copper in serum, based on the direct extraction of copper carbamate from serum with isoamyl alcohol. Burch et aa. in their method for serum iron have demonstrated that su...

A colorimetric method for determination of free fatty acids has been developed, based on the estimation of copper in a chloroform extract of their cupric salts with oxalic acid bis-(cyclohexylidenehydrazide). Contamination with inorganic copper during extraction is practically eliminated by using filter-paper pads. Specificity and interferences are discussed. Recoveries average 101.1%. Normal v...

A modification of the semiautomated assay method of Antonis (1965. J. Lipid Res. 6:307-312) for free fatty acid is presented. Free fatty acids are extracted from serum or plasma into di-n-butyl ether-2-methoxyethanol; the extract is almost free from phospholipids. The acids are analyzed in a portion of extract by a copper soap method using diphenylcarbazide. The extractant, being less dense tha...

a simple and reproducible method for the rapid extraction and determination of trace amounts of copper(ii) ions using octadecyl-bonded silica membrane disks modified by 1-(2-pyridyl azo)2-naphtol(pan) and atomic absorption spectrometry was presented. the method was based on complex formation on the surface of the envi-18 disk tm disks followed by stripping of the retained species by minimum amo...

Modern hydrometallurgical techniques have been adopted to produce high-purity gold. Many extractants were used for the extraction of gold from various synthetic solutions from which DiButyl Carbitol (DBC) had a unique superiority. Kinetics of process was studied in this paper and the influence of several parameters such as stirring speed, agitation time, impeller type, interfacial area, [Au...

Nanoporous carbons (CMK-3) were prepared and have been used as a fiber coating for headspace solid phase microextraction (HS-SPME). The prepared materials were characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and N2 adsorption/desorption isotherms. The efficiency of the fiber was evaluated using a gas chromatography (GC) system for the extraction of benzene (B) and c...

Copper-bearing raw materials are often subjected to organic solvents with main ligands as their water insoluble amine complexes. In most cases, selective extraction is a more economical and practical method because it requires simple equipment and fewer stages than other methods described in the literature1−4. Solvent extraction enjoys a favored position among the separation techniques because ...