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The proton exchange kinetics between dormant spores of Bacillus subtilis and aqueous environment are investigated using time-resolved micropotentiometry. The analysis show that the carboxyl groups in the core matrix are the major proton binding inonizable groups whose effect can be weakened by increasing the concentration of added protons.

The concept of an ion-sensitive hydrogel ionic reservoir is demonstrated for hydrogel particles of three different size ranges. On the basis of the experimental results, a two-step mechanism affecting the kinetics of proton uptake into the hydrogel particles with ionizable groups is proposed, first being the fast binding of ions to the immediate surface of each particle and second, a slower successive diffusion of bound sites into the nest inner layer of polymer network.

Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6Ps and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K ≤ T ≤ 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at TC = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K. [ABSTRACT FROM AUTHOR]