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Detailed numerical simulations of intrinsic Josephson junctions of high-temperature superconductors under external electromagnetic radiation are performed taking into account a charge imbalance effect. We demonstrate that the charge imbalance is responsible for a slope in the Shapiro step in the IV-characteristic. The value of slope increases with a nonequilibrium parameter. Coupling between junctions leads to the distribution of the slope's values along the stack. The nonperiodic boundary conditions shift the Shapiro step from the canonical position determined by Vss = hf /(2e), where f is a frequency of external radiation. This fact makes the interpretation of the experimentally found Shapiro step shift by the charge imbalance effect ambiguous.

The transparent thermoluminescent aluminum oxide-based glass of 15Al O -35P O -25CaO-25Na CO , abbreviated as APCN (all in mol%) doped with different concentrations of SiO from 0.0-500 ppm was prepared using a conventional melt-quenching technique. The TL sensitivities of the prepared glasses were investigated at 3 Gy γ-dose using a Co source and measured at a heating rate 10 C/sec. The highest TL intensity of the material doped with SiO was found at a concentration of 500 ppm (APCNSi ). Deconvolution of the glow curve from APCNSi resulted in four peaks at about 161, 194, 237 and 293 C with a Figure Of Merit (FOM) of 1.28%. The APCNSi specimen had the best dosimetric properties when compared with the other samples. Reproducibility, repeatability, dose-response curve and fading effect were checked for peak 3, which appeared at about 237 C. The results displayed that the APCNSi glass system was a low-Z material (Z ≈ 10), and had good reproducibility and good repeatability. Peak 3 showed good linearity over a dose range up to 20 Gy (R = 0.999) and sublinearity behaviour was found. The signal from APCNSi faded by about 11% after 2 days post irradiation, therefore it showed almost no significant loss. Such properties make the newly prepared glasses suitable for and highly recommended for use in γ-dosimeters. Copyright © 2016 John Wiley & Sons, Ltd.

A radon calibration chamber with variable and controlled radon concentration, humidity, and temperature was constructed and used to extend the calibration range of open-faced and diffusion-barrier charcoal canisters for higher temperature and humidity applications. The optimum exposure time to achieve the best detection accuracy and the lowest minimum detectable level was between 2 and 4 d depending on relative humidity for open-faced canister and 4 d for diffusion barrier canister over a range of humidity. The dependence of radon adsorption on the temperature was also studied for both types of canister at different values of relative humidity. The open-faced canisters at 15 degrees C absorb 68% more radon than at 30 degrees C over the range of humidity from 20% to 80%. The diffusion-barrier canister shows insignificant variation in absorption over the same range of temperature and humidity.

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