[en] Direct measurements of the yield of hydrated electrons in aqueous solutions and solvated electrons in alcohols were carried out using a stroboscopic picosecond pulse radiolysis system. The yield of solvated electrons was obtained by simultaneous consideration of the pulse shape and radiation doses. The yield at 30 ps after irradiation, G(esub(aq)^-)sub(30ps), was determined to be 4.8 +- 0.3 products per 100 eV as compared to the G(esub(aq)^-)sub(100ns) of 2.7. Experimental values, including the present ones, are higher by 0.3 than the theoretical ones calculated using the spur diffusion model in the time period from 3 x 10^-11 to 10^-8 s. Nevertheless, both results show a quite similar time dependence, i.e., fast decay of hydrated electrons in spur reactions. The G-values of solvated electrons at 30 ps were also determined in alcohols. The G-value of solvated electron is 3.4 +- 0.3 in both methanol and ethanol, 2.0 +- 0.3 in 1-propanol and 2.3 +- 0.3 in ethylene glycol. (author)