Bu-Ali Sina University

About: Bu-Ali Sina University is a education organization based out in Hamadan, Hamadān, Iran. It is known for research contribution in the topics: Catalysis & Adsorption. The organization has 4078 authors who have published 7969 publications receiving 122828 citations.

Distribution of Heavy Metals around the Dashkasan Au Mine

Abstract: The aim of the study is to determine the major source and extent of metal pollution in the vicinity of Dashkasan gold mine. Dashkasan mine has resulted in extensive contamination of soils by Arsenic (As) and potentially toxic ore-related elements including Mercury (Hg), Antimony (Sb) and Cadmium (Cd). Soils samples were collected and analyzed for As, Cd, Hg, Pb and Sb. The concentration of each heavy metal is controlled by different parameters (soil pH, iron and aluminum oxide content, clay content, organic matter and cation exchange capacity). The maximum content in the soils were 485, 3.2, 100, 2710 and 640 mg/kg for As, Cd, Hg, Pb and Sb, respectively. In particular, the extracted concentration of As, Cd, Hg and Sb are in excess of the tolerable levels. Positive correlation with organic matter and clay content but not with pH has been observed for most of elements analyzed in this study. Enrichment factor (EF) analysis and cluster analysis (CA) highlighted the lithogenic origin of heavy metals. It also revealed the need for detailed geochemical surveys in the future in order to decrease the uncertainty of discrimination between lithogenic and anthropogenic origin of metals of interest.

Synthesis of a novel dendrimer core of oxo-vanadium phthalocyanine magnetic nano particles: as an efficient catalyst for the synthesis of 3,4-dihydropyrano[c]chromenes derivatives under green condition

Abstract: A new magnetically recoverable nanocatalyst was synthesized by covalent binding of an amino vanadium oxo phthalocyanine, on the surface of silica coated magnetite nano particles with 3-chloropropyl moieties. Full characterization of the prepared nano catalyst was performed with different physicochemical methods such as FT-IR spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscope (AFM), and thermal gravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometry (VSM), Brunauer–Emmett–Teller (BET), X-ray fluorescence (XRF) and inductively coupled plasma (ICP). Finally, catalytic activity of the prepared Fe3O4@SiO2@SiO2(CH2)3@AVOPc was examined in the synthesis of 3,4-dihydropyrano[c]chromenes derivatives. The nano catalysts provided excellent catalytic activities to yield the desired products in short reaction time, mild and green conditions under solvent-free at room temperature. The catalysts could be easily separated from the reaction mixture by a magnet, and recycled eight consecutive cycles without any losing significant activities. Moreover, by this synthetic method, some novel 3,4-dihydropyrano[c]chromenes derivatives are prepared and characterized.