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It is well known that one of the factors that influence the indoor radon variability is the floor level of the buildings. Considering the fact that the main source of indoor radon is radon in soil gas, it is expected that the radon concentration decreases at higher floors. Thus at higher floors the dominant source of radon is originating from building materials, and in some cases there may be deviations from the generally established regularity. In such sense, we chose one freestanding single-family house with loft and other 16-floor high-rise residential building for this study. The indoor radon measurements were performed by two methods: passive and active. We used passive devices based on track-etched detectors: Radtrak2 Radonova. For the short-term indoor radon measurements, we used two active devices: SN1029 and SN1030 (manufactured by Sun Nuclear Corporation). The first device was fixed in the living room at the ground level and the second was moved through the floors of the residential building. Every measuring cycle at the specified floor lasted seven days with the sampling time of 2 h. The results show two different indoor radon behaviours regarding radon variability due to floor level. In the single-family house with loft we registered intense difference between radon concentration in the ground level and loft, while in the high-rise residential building the radon level was almost the same at all floors, and hence we may conclude that radon originated mainly from building materials. [ABSTRACT FROM AUTHOR]

In this paper, we present new spectroscopic information on Nb 94 from the Nb 93 (n t h ,2 γ) reaction. The intensities of the two-step gamma cascades in the compound nucleus Nb 94 to the final levels, with excitation energies below 400 keV, were derived from experimental spectra recorded at the PGAA facility of Centre for Energy Research (MTA EK), Budapest, Hungary. The intensities, energies of primary and secondary transitions of 216 energy-resolved cascades as well as intermediate cascade levels were determined. The part of the level scheme of Nb 94 was obtained from analyzing the intensity spectra of the strongest cascades. The results were compared to the existing data in the ENSDF database. We concluded that 27 primary transitions, 29 intermediate cascades levels as well as 183 secondary transitions can be recommended as new nuclear data. [ABSTRACT FROM AUTHOR]

This work provides new data about the level scheme of Mn 25 56 studied by the Mn 25 55 (n t h ,2 γ) reaction. The spectroscopic information were collected using the gamma-gamma coincidence spectrometer at the Technische Universität München, Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany. The intensities, energies of primary and secondary transitions of 71 energy-resolved cascades, as well as intermediate cascade levels were determined. The updated level scheme of Mn 25 56 was obtained from analyzing the intensity spectra of the strongest cascades. The comparison with the existing data in the ENSDF database shows that 23 primary transitions, 24 intermediate cascades levels as well as 32 secondary transitions determinated in this work can be recommended as new nuclear data. [ABSTRACT FROM AUTHOR]