The highest solar cell efficiencies are obtained with concentrating systems. However, these systems have two major drawbacks: tracking is needed and diffuse sunlight poorly absorbed. Here, a system that overcomes both limitations presented, by exploiting light-induced halide segregation in mixed perovskite films. A monolayer of silica microspheres focuses direct film below. Through phase low ba...

Quantitative analysis for food products and natural samples, to determine the activity of each radionuclide, can be made by using a high-purity germanium (HPGe) gamma-ray spectrometer system. The analysis procedure is, in general, based upon the guidelines established by the Nuclear Safety Division of the Ministry of Education, Culture, Sports, Science and Technology in Japan (JP MEXT). In the ...