Synthesis and Some Properties of Tungstophosphatozincates and Their Thermolysis Products

Russian Journal of General Chemistry - Tungstophosphatozincates with the Keggin anion structure Kt5[PW11O39Zn(H2O)]?nH2O, Kt = Rb+, Cs+, (CH3)4N+; (C2H5)4N+ were synthesized. Their...     

A study of the behavior of disubstituted methyl esters of peptide derivatives of fullerene C60 in aqueous solutions

Association of methyl esters of peptide-containing maleimidofullerenes in aqueous solutions was studied by the diffusion method. It was found that dissolution of these compounds follows a mechanism differing from that for the corresponding salts and that the degree of association of fullerene derivatives is affected most strongly by the structure of the molecule as a whole rather than by the peptide nature.     

A Phenomenological Model of the Electrical Double Layer in the Anthracite–Electrolyte System with Allowance for Energy Surface Inhomogeneity

A model for the structure of the electrical double layer taking into account the structural inhomogeneity of the solid surface was proposed. An interpretation was suggested for high capacity values of anthracites in electrolyte solutions. Calculated and experimental values of the capacity of the electrical double layer at the zero-charge potential were compared. Integrals allowing for the effect of the energy surface inhomogeneity of coals on their electrosurface properties were calculated.     

Electrical conductivity of graphite suspensions in potassium chloride solutions in direct- and alternating-current electric fields

Electrical conductivity of graphite dispersions in aqueous KCl solutions has been measured. The measurements have been performed in alternating- (1000 Hz) and direct-current electric fields. In an alternating-current electric field, at electrolyte concentrations of 0.0005–0.01 М, the conductivity increases as depending on the mass fraction of the dispersed phase. In 0.1 М solutions, a decrease in the conductivity of the suspension is followed by an increase at dispersed phase contents of higher than 15 wt %. In a direct-current electric field, the conductivity of graphite suspensions (0.001–0.01 М KCl) varies slightly and increases at dispersed phase contents of higher than 15 wt %. In 0.1 М solutions, the specific conductivity of the suspension initially decreases and, then, increases at dispersed phase concentrations above 15 wt %. The unusual electrical properties of the suspensions have been explained as being results of variations in the capacitive and active components of the conductivity of graphite dispersions in electrolytes within the framework of a topological model. Particle polarization and a relatively high capacitive component of the conductivity mainly contribute to an increase in the conductivity of the suspensions in 0.0005–0.01 М electrolytes in the alternating-current electric field. A decrease in the conductivity of suspensions in 0.1 М electrolytes is due to a negative difference between the capacitive and active components of the specific conductivity. It has been assumed that the aggregation of graphite particles yields conducting structures at dispersed phase concentrations above 15 wt %.