an efficient synthetic method for successful synthesis of amine denderon on sba-15 and related pd (ii) complex has been developed. this modified mesoporous material was characterized by various techniques such as tem, xrd, atomic absorption spectroscopy, n2 adsorption-desorption, and ft-ir. the catalytic activities of the prepared catalysts were investigated by employing aerobic oxidation of al...

In this paper we examine the absorption and dispersion properties of a weak probe field via Electromagnetically Induced Transparency (EIT) in a four-level system. It is shown that under certain condition, using this model, the absorption cancellation is appeared and the medium becomes transparent to the weak probe field. It will be shown that the controlling of absorption and dispersion spectru...

A novel, simple, sensitive and effective method has been developed for preconcentration of the trace Pb (II) ions in aqueous Samples by CNT carboxyl which in order to improve the performance of extraction and preconcentration was used. Amounting of the ions density in solution was performed by the method of flame atomic absorption spectrometry. The effective parameters on extraction such as: ef...

Single-molecule force spectroscopy with an atomic force microscope has been widely used to study inter- and intramolecular interactions. To obtain data consistent with single molecular events, a well-defined method is critical to limit the number of molecules at the apex of an AFM probe to one or to a few. In this paper, we demonstrate an easy method for single-molecule probe modification by us...

anzali international wetland is one of the most valuable water resources as registered in ramsar convention with an extent of about 150 km2 in the south caspian sea. this wetland, not only has ecological and biological importance for migratory birds and rare fish species, but also is used for farms to discharge into the caspian sea through this wetland. therefore its pollution control is very i...

a simple, highly sensitive, accurate and selective method for determination of trace amounts of cu2+ in water samples .in this paper, chitosan was used to encapsulate nano-fe3o4 and produce a nano-fe3o4-chitosan sorbent based new sorbent was prepared. this was treated with ethylenediamine (ed) in another solvent-free procedure for the formation of a novel nano-fe3o4-chitosan-ed.flame atomic abs...

a simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (dllme) was developed for determination and speciation of trace amounts of chromium (cr) by flame atomic absorption spectrometry (faas). in the proposed approach, chloroform and methanol were used as extraction and dispersive solvents. a new schiff's base ligand, bis(2-methoxy benzaldehyde) ethylene d...

heavy metals are highly poisonous in the environment, even in small quantities, and endanger certain species and all live beings. current methods of removing heavy metals from aqueous media include chemical sequestration, ion exchange, surface absorption, membrane processes, oxidation and revival procedures which have high investment and exploitation costs. hence, it is significantly necessary ...