A tremendous amount of radioactivity was discharged because of the damage to cooling systems of nuclear reactors in the Fukushima No. 1 nuclear power plant in March 2011. Fukushima and its adjacent prefectures were contaminated with fission products from the accident. Here, we show a geographical distribution of radioactive iodine, tellurium, and cesium in the surface soils of central-east Japan as determined by gamma-ray spectrometry. Especially in Fukushima prefecture, contaminated area spreads around Iitate and Naka-Dori for all the radionuclides we measured. Distributions of the radionuclides were affected by the physical state of each nuclide as well as geographical features. Considering meteorological conditions, it is concluded that the radioactive material transported on March 15 was the major contributor to contamination in Fukushima prefecture, whereas the radioactive material transported on March 21 was the major source in Ibaraki, Tochigi, Saitama, and Chiba prefectures and in Tokyo.

Compressively strained SrTaO2N thin films were epitaxially grown on SrTiO3 substrates using nitrogen plasma-assisted pulsed laser deposition. Piezoresponse force microscopy measurements revealed small domains (101–102 nm) that exhibited classical ferroelectricity, a behaviour not previously observed in perovskite oxynitrides. The surrounding matrix region exhibited relaxor ferroelectric-like behaviour, with remanent polarisation invoked by domain poling. First-principles calculations suggested that the small domains and the surrounding matrix had trans-type and a cis-type anion arrangements, respectively. These experiments demonstrate the promise of tailoring the functionality of perovskite oxynitrides by modifying the anion arrangements by using epitaxial strain.

The elements Fe, Zn, and Pb were also present. It has since been reported that very similar micron-scale spherical particles have been found 20 km northwest and 3 km south of the F1NPS (Satou et al., 2016; Furuki et al., 2017). Similar particles were isolated from dust on nonwoven fabric cloth and needles of Japanese cedar (Yamaguchi et al., 2016; Kogure et al., 2016). This revealed that such Cs-bearing particles were widely dispersed within the Fukushima region. Although their origin could be attributable to any of the various release events that occurred at the F1NPS, the exact source of the radionuclides is unclear. In this study, roadside soil and dust samples from the immediate vicinity of the F1NPS were analyzed using scanning electron microscopy (SEM), EDS, synchrotron radiation micro-beam X-ray fluorescence (SR-m-XRF) analysis, and gamma spectrometry, with the aim of attributing sources to them. MATERIALS AND METHODS Sampling location Soil and dust samples were collected within the highly

Global cooling in intermediate glacial climate with northern ice sheets preconditions climatic instability with bipolar seesaw.

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