We propose here a new class of fluorescent H(+) turn-on oxazinoindoline (Ox) dyes as chromoionophores suitable for the development of polymeric ion-selective membranes. Through rational design, oxazinoindolines with varying basicities and tunable absorption bands that extend to the near-infrared region were prepared. The basicities of the compounds were evaluated by potentiometry and fluorescen...

The stability of a Ag/AgCl reference electrode equipped with a gelled ionic liquid, 1-methyl-3-octylimidazolium bis(trifluoromethanesulfonyl)amide (C(8)mimC(1)C(1)N), as a salt bridge, was examined in the potentiometry of pH standard solutions. The variation in the liquid junction potential (LJP) of the ionic liquid (IL)-type reference electrode, measured with respect to a double junction-type ...

The effective charge Z* is often invoked to account for the accumulation of counterions near the colloid with intrinsic charge Z. Although the ion concentrations c(i) are not uniform in the solution due to the presence of the charged particle, their chemical potentials are uniform everywhere. Thus, on the basis of ion chemical potential, effective ion concentrations c(i)*, which can be experime...

The electrochemical formation of Neodymium–Nickel (Nd–Ni) alloys was investigated in a molten CaCl 2 –NdCl 3 (1.0 mol%) system at 1123 K. Cyclic voltammograms for Molybdenum (Mo) and Ni electrodes showed the electrodeposition/dissolution metallic Nd formation/dissolution Nd–Ni alloys, respectively. equilibrium potential 3+ /Nd determined 0.27 V (vs. Ca 2+ /Ca) by open-circuit potentiometry Mo e...

1, 3-Bis(2-cyanobenzene)triazene, L, was used as a suitable ionophore for the fabrication of a new PVC-based polymeric membrane coated graphite electrode for selective sensing of Cd2+ ion. The electrode exhibited a selective linear Nernstian response to Cd2+ ion at an optimal pH range of 6-9 with a limit of detection of 8.0 × 10-6 M and a fast response time of about 2 s. The electrode was used ...

The thermodynamic stability of the metallacrown complexes formed by picolinehydroxamic acid (Picha) with Cu(ii), Ni(ii) and Zn(ii) in aqueous solution has been determined by potentiometry, and the speciation models were validated by ESI-MS and UV-visible spectrophotometry. Cu(ii) and Zn(ii) form 12-MC-4 species as the unique metallacrowns present in the solution. While for Cu(ii) the 12-MC-4 is...

The reaction between phenothiazine and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in the presence of p-toluenesulfonic acid in chloroform was investigated by potentiometry, voltammetry and spectrophotometry, and the reaction pathways were proposed. The conditions for the oxidimetric titration of phenothiazines with a standard chloroform solution of DDQ were optimized and the potentiometric...