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A tentative statistical analysis and comparative plots of the data from sets of PWAS transducers revealed that the trends observed on an individual PWAS are also observed on the entire set of PWAS transducers. The article concludes with a summary, conclusions, and suggestions for further work.

Concrete of various type have been used extensively for the adequate shielding of the radiological equipment using X and gamma rays. In its basic form, concrete is composed of pieces of inert aggregate held together by hardened cement paste. Dierent concrete types with special cements have been prepared. The linear attenuation coecients of conventional concrete and concrete with supplementary mineral additives (barite and witherite) at dierent gamma energies (Co-60: 1.25 MeV, Cs-137: 0.662 MeV, Ir-192: 0.37 MeV) in narrow beam conditions have been measured. This paper includes some experimental data regarding the inuence of barite and witherite additives on photon attenuation coecients of concrete.

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SYNOPSISIonizing radiation induces various changes in the molecular structure of elastomers; consequently, the macroscopic properties of the irradiated elastomers will be modified. The newly formed products and the alteration of the initial chemical structure are the result of free-radical reactions which provide the crosslinking and/or the depolymerization of the tested materials and destructive simultaneous processes involving diffused aggressive agents. This paper describes the behavior of butyl and chlorinated and brominated butyl elastomers under the action of gamma radiation for total doses up to 0.5 MGy. The experimental data provided by several procedures emphasize a complex chemistry circumstance consisting of the simultaneous crosslinking and scission of the macromolecular chains and consecutive processes involving free radicals. Evaluation of the studied changes was via gel content, oxidation level, unsaturation, and halogen distribution as dependent on the total radiation dose. The mechanism of the degradation and a relationship between the crosslinking/ scission ratio and the absorbed dose are discussed.

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Accelerator Mass Spectrometry and Full Combustion method followed by liquid scintillation counting were applied to measure the accumulated 14C in the thermal column of the decommissioned VVR-S reactor in NIPNE Bucharest.