Plastic vs. Liquid Scintillation for 14C radiotracers determination in high salt matrices

Crosslinked plastic scintillators: A new detection system for radioactivity measurement in organic and aggressive media

“…The mean detection efficiency under the final conditions was 39.5 AE 1.0% for 14 C, which is closer to that commonly obtained with PS microspheres [12,29] but with the spectra located at lower energies. In addition, it is important to note that the three polymerisations produce similar detection efficiencies, the relative standard deviation was 2.6%, also, the blank values were 0.9184 AE 0.0911 cpm, and polymerisation yields, 92.4 AE 0.8%, indicating the adequate reproducibility between the three polymerisations performed.…”

“…Five increasing ratios of PPO ranging from 1 to 15% were studied. Table 1 (entries [21][22][23][24][25][26][27][28][29][30] shows that the detection efficiency increases and the spectrum position shifts slightly to higher energies when the proportion of PPO increases up to 6%. After this limit, the detection efficiency remains constant.…”

“…After preparation, the vials were shaken by ultrasound for 2 min to remove the air and then centrifuged for 10 min at 5000 rpm to package the microspheres Table 1 Composition of the different polymers synthesised as well as the detection efficiency and SQP(E) values obtained in the measurement of 14 All polymers produce microparticles except entries 1-4, 47, 48 and 50 that produces bulk. [21]. The final activities in the measurement vials were approximately 33 Bq for the study of the composition effect and approximately 3 Bq for the characterisation studies except for 3 H, which was approximately 67 Bq.…”

“…In addition, the plastic scintillator can be used as support for the separation steps and due to the intrinsic heterogeneity of the PS -sample mixture, it can be used for the measurement of samples with a high salt content [9][10][11][12]. However, this technique also exhibits some drawbacks, such as a low detection efficiency when low energy beta emitters are measured ( 3 H) due to the higher distance between the sample and the scintillator.…”

Systematic study of particle quenching in organic scintillators

“…PSm are a solid mixture of organic fluorescent molecules in a completely polymerized solvent (e.g., polystyrene or polivinyltoluene) and have a size that is in the tens or hundreds of microns. The aqueous sample can be mixed with the PSm to obtain a heterogeneous scintillation medium, which presents some advantages over LS (e.g., Scintillation proximity assay [14], continuous measurements [15,16], non-production of mixed waste [17][18][19] and others [20,21]). It can be assumed that the scintillation mechanism of PSm must be similar to that of LS, but previous experiments [22] have demonstrated that the loss of energy during the path of a particle through the sample until it arrives to the scintillator is of high importance because it causes an important decrease in the detection efficiency for weak beta emitters (e.g., 3 H).…”