Pulse radiolysis dosimetry

The first pulse radiolysis experiments to measure G°(e ) directly were made in the 1970s, with reported values of 4.0 0.2 molecules (100 eV) at 30 psec [45] and 4.1 0.1 molecules (100 eV) at > 200 psec [46]. The latter value was subsequently revised to 4.6 0.2 molecules (100 eV) at 100 psec [47], and later a yield of 4.8 0.3 molecules (100 eV) at 30 psec was reported by Sumiyoshi et al. [48]. The method of evaluating G(e ) at these short times is either to use dosimetry [45,46] and the molar absorption coefficient of e, or to compare the optical absorbance at short times with that observed at 10 -10 sec and take G(e q) = 2.7 molecules (100 eV) at this time [48]. The causes of the discrepancies between these pulse radiolysis values have been reviewed recently by Bartels et al. [49], who have also made new measurements of the spur decay of e. ... 

Schuchmann H-P, Deeble DJ, Phillips GO, von Sonntag C (1991) Pulse radiolysis with conductometric detection two approaches to absolute dosimetry. Radiat Phys Chem 37 157-160 Schuchmann MN, Schuchmann H-P, von Sonntag C (1989) The pJCa value of the O2CH2CO2H radical the Taft a constant of the -CEi202 group. J Phys Chem 93 5320-5323 Schuler RH, Hartzell AL, Behar B (1981) Track effects in radiation chemistry. Concentration dependence for the scavenging of OH by ferrocyanide in N20-saturated solutions. J Phys Chem 85 192-199... 

In the following text, a few dosimeter systems will be mentioned that are commonly used in radiation chemistry. For a more detailed treatment of chemical and physical dosimetry, see O Chap. 49 in Vol. 5 on Dosimetry Methods. However, more attention will be paid to pulse dosimetry that is used in pulse radiolysis investigations. 

In pulse radiolysis, the dose measurement should be carried out in the measuring cell under identical conditions with the experiments. Therefore, for dosimetry purposes it is advisable to use the same detection system that is also utilized in the measurements. In practice mostly the thiocyanate dosimeter and, less frequently, the hydrated electron dosimeter is used in pulse radiolysis studies (Fielden 1982). 

Fielden EM (1982) Chemical dosimetry of pulsed electron and X-ray sources in the 1-20 MeV range. In Baxendale JH, Busi F (eds) The study of fest processes and transient species by electron pulse radiolysis. Reidel, Dordrect, pp 49-62 Flamigni L, Barigelletti F, Dellonte S, Orlandi G (1982) Chem Phys Lett 89 13... 

Karoiczak S (1999) Pulse radiolysis—experimental features. In Mayer J (ed) Properties and reactions of radiation induced transients. Selected topics. Polish Scientific Publishers, rsza, pp 5-37 Kase KR, Bjangard BE, Attix FH (1985) The dosimetry of ionizing radiation, vol I and II. Academic, Orlando... 

Pb(CH3)4 vapor has been used to fill Geiger counters [170 to 174], and was suggested for use in liquid ionization chambers [175]. Short-lived transients are generated by pulse radiolysis of Pb(CH3)4 dosed with naphthalene and toluene, which can be employed for time-resolved dosimetry of low-energy X-rays [176]. 

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