The formation constants of the species formed in the systems H+ + cytidine 5-monophosphate (CMP)and H+ + cytidine 5-monophosphate + Tl (I) ion have been determined in aqueous solution in a widepH range of 1.5 to 10.5 at 25 °C and different ionic strengths ranging from 0.1 to 1.5 moldm-3NaClO4, NaNO3, and NaCl using potentiometric-spectrophotometric technique. The composition ofthe complexes was...

The complexation reactions between 4-(2-pyridy1azo)-resorcinol and Cd ,H g and Pb io ns have been investigated in acetonitrile-dimethyEomamide mixtures at various temperatures using a spectrophotometric technique. The stoichiometry and the formation constants of the complexes formed in solution were calculated by computer refinement of absorbance-mole ratio data using nonlinear least-square ...

Study was made of host-guest complexation of neutral crown ethers with fiveand six-membered Nheteroaromatic cations and purinium cation. Complexation of tetraphenylborate with selected Nheteroaromatic cations and tropylium cation also was studied. Crown ether complexes were characterized by mass spectrometric and 1H NMR spectrometric methods and by X-ray crystallography. Fast atom bombardment m...

where the values of the forward (kd) and reverse (kp) rate constants may be different from those in the ground state because of differences in the properties of the 2-naphthol in these two states (for example, Ka 6= K ∗ a in part I). The objective of this experiment is to determine the deprotonation/protonation rate constants of 2-naphthol in its lowest excited singlet state in aqueous solution...

Potentiometric measurements of Yttrium and Rare Earth Element (YREE) complexation by carbonate and bicarbonate indicate that the quality of carbonate complexation constants previously obtained via solvent exchange analyses are superior to characterizations obtained using solubility and adsorptive exchange analyses. The results of our analyses at 25°C are combined with the results of previous so...

The ligand triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetamide (ttham) was synthesized with the aim of forming lanthanide complexes suitable as contrast agents for magnetic resonance imaging applications utilizing the chemical exchange-dependent saturation transfer (CEST) effect. It was designed to exclude water molecules from the first coordination sphere and provide a high number of CEST ...

apotransferrin (apo tf)  in 0.1 m n-(2hydroxyethyl)piperazine-n2-ethanesulfanic acid at 25 ˚c  and ph 7.4 has been titrated with acidic solution of tb3+. the binding of tb3+ at  the two specific metal-binding sites of transferrin was followed from the changes in the difference uv spectra at 245 nm. the molar absorptivity per binding site for tb3+-tf is 22,500 ± 1000 m-1cm-1. to determine the tb...

In the frame of a systematic study on sequestering ability natural antioxidants towards metal cations, complexation coumarin-3-carboxilic acid (HCCA) with neodymium(III) and dioxouranium(VI) (uranyl, UO22+), overall stability constants resulting complexes, were evaluated from pH-potentiometric titration data at 37 °C in an aqueous solution (i.e., 0.16 mol/L NaClO4). The graphic representation c...