Polarographic Behaviour of the Hexa-ammine-chromium(III) Ion: Role of Hydrogen Ions
HEXA-AMMINECHROMIUM(III) ion in acetate buffer solutions is reduced at the dropping mercury electrode, and gives two polarographic waves. The first wave, which is well defined, is considered to be a one-electron reduction of Cr(III) to Cr(II)1. Its half-wave potential at 25° C was found to be −0.970 V versus saturated calomel electrode in 0.1 M acetate buffer solution which contained 0.9 M potassium chloride and 0.005 per cent gelatin (Fig. 1, curve a). The limiting current of this wave was diffusion-controlled and proportional to the concentration of the complex ion up to 5 mM. Both the half-wave potential and the diffusion current remained constant when the pH was varied from 4.5 to 5.45. No change was observed when potassium chloride was replaced by ammonium chloride at the constant ionic strength. The plot of log ī/(īd − ī) versus E, where ī means the average current, īd the average diffusion current, and E, the potential of the dropping mercury electrode, gave a straight line with a reciprocal slope of 64 mV, whereas the examinations with Kalousek's circuit and alternating current polarograph showed that this wave has nearly irreversible character.
Ion-pair Formation of Some Substitution-inert Complexes and Sulfate Ions. Determination of Association Constants Using Polarographic Diffusion Current
The polarographic diffusion current of some tervalent substitution-inert complex cations decreases by the addition of sulfate. From the change in diffusion current the association constants of substitution-inert complex and sulfate ions are obtained at ionic strength 0.1 (NaClO4) and 25°C. The values are 69±8, 58±8 and 4×10 for [Co(NH3)6]3+–SO42−, [Cr(NH3)6]3+–SO42− and [Cr(H2O)6]3+–SO42 respectively. The formation of [Co(NH3)6]3+–HSO4− is negligibly small compared with that of [Co(NH3)6]3+–SO42−.
A numerical study on liquid ring motion and fragmentation for the initial process of liquid explosive dispersal
For the explosive dispersal on liquid fuel of FAE technique, the expansion of gaseous detonation products, axisymmetric radial extension and fragmentation of a liquid ring were analyzed, then corresponding models were established. By those models coupled, the numerical simulation on motion and fragmentation of the liquid ring exerted by strong action was carried out. The results computed show that the models established are feasible, and present study can offer initial conditions for the numerical simulation on the process of liquid secondary breakup and gas-liquid mixing.