جستجوی مقالات مرتبط با کلیدواژه "thallium" در نشریات گروه "شیمی"

Thallium is a water-soluble metal and extra dosage has toxicological effect in human body. Thallium is readily absorbed by inhalation, ingestion and skin contact. The symptomatology of thallium toxicity was seen in patients with hemorrhage, bone/gastrointestinal problems, delirium, convulsions and coma. So, accurate determination of thallium in water and human urine is necessary. In this research, a novel and applied method based on 25 mg of nanomagnetic 4-Aminothieno[2,3-d] pyrimidine-2-thiol functionalized on graphene oxide (Fe3O4-ATPyHS@GO) was used for thallium extraction in 50 mL of water, wastewater and urine samples by dispersive magnetic micro solid-phase extraction (DM-μ-SPE). After extraction and back-extraction of solid phase by 1 mL of nitric acid solution, the concentration of thallium ions determined by flame atomic absorption spectrometry (F-AAS). The working/linear range, the limit of detection (LOD), and preconcentration factor (PF) were achieved (4-1400 μgL−1; 4-300 μg L−1), 0.9 μg L−1, and 50, respectively (Mean RSD%=1.8 water; 2.1 urine). The absorption capacity of GO and Fe3O4-ATPyHS@GO adsorbent were achieved 7.2 mg g-1 and 137.5 mg g-1 for 5 mg L-1 of thallium, respectively. The procedure was validated by ICP-MS analyzer.

The podand chelate, 1,2-bis[2' -(8" -oxyquinoline)ethoxy]-benzene have been synthesized and used as a neutral ionophore to construct an ion selective electrode for the potentiometric determination of thallium ions. Due to the decisive role of solvent mediators, the membranes was fabricated with the plasticizers o-NPOE, DBP, DBBP, TEP, OA, DOP, CN respectively and anionic additive NaTPB. The best of the results were obtained with the membrane electrode composition of o-NPOE:PVC:Ionophore:NaTPB (58%:34%:5%:3%). This sensor exhibits Nernstian response with slope 58.7±0.3 mV decade-1 of activity in concentration range 2.0×10-9 to 1.0×10-1 M Tl(I), performs satisfactorily over wide pH range (2.5-12), with a fast response time (5 s). The sensor was also found to work satisfactorily in partially non-aqueous media up to 40% content of methanol, ethanol, acetone and acetonitrile solution. The Tl(I)-selective electrode was used as an indicator electrode for the titration of TlNO3 with EDTA and KI solution. The selectivity coefficients determined by using fixed interference method (FIM) indicate high selectivity for Tl (I).