In this work, we developed a method based on ultrasound-assisted emulsification microextraction (USAEME) for the determination of zinc and copper by flame atomic absorption spectrometry (FAAS). The method is based on the use of the organic solvent carbon tetrachloride (CCl4) as an extraction solvent. In order to obtain a high enrichment factor, the effect of different parameters affecting the c...

In this current report, a simple, reliable, and rapid method based on modifying the cellulose surface by doping it with different percentages of lanthanum hydroxide (i.e., 1% La(OH)3-cellulose (LC), 5% La(OH)3-cellulose (LC2), and 10% La(OH)3-cellulose (LC3)) was proposed as a selective marker for detection of copper (Cu(II)) in aqueous medium. Surface properties of the newly modified cellulose...

The reduction of Cu(II) oxide species in siliceous matrixes of different porosity (MFI, FAU, MCM-48) and in alumosilicate MFI was studied by temperature-programmed reduction in hydrogen (TPR), by X-ray absorption fine structure (after stationary hydrogen treatments), and by transmission electron microscopy. It was found that the reduction may proceed in one or in two reduction steps. The two-st...

The title copper(II) complex, {(C27H37N2)[Cu4(CH3COO)8Cl]·3CH2Cl2} n , is a one-dimensional coordination polymer. The asymmetric unit is composed of a copper(II) tetra-acetate paddle-wheel complex, a Cl(-) anion situated on a twofold rotation axis, half a 1,3-bis-(2,6-diisoprop-ylphenyl)imidazolium cation (the whole mol-ecule being generated by twofold rotation symmetry) and one and a half of a...

the interaction between some heavy metal ions such as of pb(ii), cd(ii) and cu(ii) ions from aqueous solution adsorbed by single walled carbon nanotube (swcnts) and carboxylate group functionalized single walled carbon nanotube (swcnt-cooh) surfaces were studied by atomic absorption spectroscopy. the effect of contact time, ph, initial concentration of ion, ionic strength and temperature on the...

The E. coli copper resistance protein PcoC enhances survival of a bacterium under conditions of extreme copper stress. This small protein has no cysteines, but does have an unusual methionine-rich sequence motif, suggesting that methionine ligation may be important in Cu binding. It is shown that PcoC binds both Cu(I) and Cu(II), in addition to binding Hg(II) and Ag(I). Previously crystallograp...

BACKGROUND Haemophilus ducreyi has emerged as a major cause of cutaneous ulcers (CU) in yaws-endemic regions of the tropics in the South Pacific, South East Asia and Africa. H. ducreyi was once thought only to cause the genital ulcer (GU) disease chancroid; GU strains belong to 2 distinct classes, class I and class II. Using whole-genome sequencing of 4 CU strains from Samoa, 1 from Vanuatu and...

In the title complex, [Cu(2)Cl(4)(C(17)H(22)N(2))(2)], the Cu(II) cation is coordinated by a N,N'-dibenzyl-propane-1,2-diamine ligand and two Cl(-) anions, and a Cl(-) anion from an adjacent mol-ecule further bridges to the Cu(II) cation in the apical position, with a longer Cu-Cl distance of 2.9858 (18) Å, forming a centrosymmetric dimeric complex in which each Cu(II) cation is in a distorted ...

The synthesis of ligand L based on a 2,6-bis[(N,N-bis(methylene phosphonic acid)aminomethyl] pyridine scaffold is described. Potentiometry combined with UV-Vis absorption spectrophotometric titrations were used to determine the protonation constants of the ligand and the stability constants of its corresponding Cu(II), Ni(II), Zn(II) and Ga(III) cations (0.1 M NaClO(4), 25.0 °C). The physico-ch...