Radon is a unique natural element because it is an inert gas and at the same time radioactive in all of its isotopes. It is known fact that exposure of the population to high concentrations of radon gas leads to irradiation of primarily respiratory organs which can cause lung cancer. Radon is a subject of intense research around the world in order to, among other reasons, assess the risk of exposure and develop appropriate standards of protection and its control. By coal mining and exploitation, radioactive radon gas, which is captured in natural geological structures, is relocated from the deep coal layers. Hence, it is concentrated in the depots and coal seams of the mines or being transported to the surface of the earth where it can significantly change the levels of radioactivity in the working premises and residences. This chapter presents the results of a 3-year research of radon activity concentration and gamma dose rate in the air in underground and surface coal mines of Bosnia and Herzegovina.

Abstract With gamma spectrometric method 23 samples of mineral and thermal waters of Bosnia and Herzegovina were analyzed. Activity concentrations of the investigated radionuclides were in the range 12–346 mBq·L−1 for 40K, 1.1–791 mBq·L−1 for 226Ra, 0.2–221 mBq·L−1 for 228Ra, 13–367 mBq·L−1 for 238U, and 0.6–17 mBq·L−1 for 235U. For all investigated radionuclides annual effective dose was estimated. The estimated total annual committed effective dose received by population as a result of ingestion of water was in the range 0.11–2.51 μSv·y−1 for thermal water and in the range 0.11–38.8 μSv·y−1 for mineral water. Measurement of activity concentrations of natural radionuclides in the examined samples was carried out with a gamma-spectrometer with high-purity germanium (HPGe) detector, having a relative efficiency of 70%.

This document refers to the non-stationary heat conduction through transparent thermal insulators. Non-stationary heat transfer means that temperature varies in time, in all points of the thermal field. Temporal and spatial distributions of the temperature inside of the sample are experimentally determined.

This paper explains passive collection of solar radiation energy using transparent thermal insulators. Transparent thermal insulators are transparent for sunlight, at the same time those are very good thermal insulators. Transparent thermal insulators can be placed instead of standard conventional thermal insulators and additionally transparent insulators can capture solar radiation, transform it into heat and save heat just as standard insulators. Using transparent insulators would lead to reduce in usage of fossil fuels and would help protection of an environment and reduce effects of global warming, etc.