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Hackmanites, a variety of sodalite with the general formula Na8Al6Si6O24(Cl,S)2, are a family of nature‐based smart materials having the ability for reversible photochromism upon UV or X‐ray exposure. Being nontoxic, cheap, and durable, hackmanite would be an optimal material for the visual detection of the presence of X‐rays in simple portable systems. However, its X‐ray‐induced coloring abilities are so far known only qualitatively. In this work, a combination of experimental and computational methods is used to reveal the mechanism of X‐ray‐induced color changing in these materials. Finally, their use is demonstrated both in color intensity‐based X‐ray dosimetry and photochromic X‐ray imaging. [ABSTRACT FROM AUTHOR]

The colossal magnetoresistive insulator to metal switching of almost nine orders of magnitude under the significantly reduced magnetic field is achieved by illumination for the low bandwidth manganite thin films. Similarly, by changing the measuring bias voltage through the sample the required magnetic field for insulator-metal transition can be further fine-tuned. By applying a magnetic field of suitable strength, the samples can also be tuned to be extra sensitive to the illumination having colossal effect on the resistivity at low temperatures. This kind of utilizing of multiple external stimulants, which together change the properties of the material, could have significant impact on the new generation of phase-change memories working under affordable conditions. [ABSTRACT FROM AUTHOR]

Hall coefficient, electrical conductivity, and electron mobility are investigated for n-ZnSe:Yb single crystals with high concentration of electrically active background impurities (( [ABSTRACT FROM AUTHOR]

Recombination of the primary radical pair of photosystem II (PSII) of photosynthesis may produce the triplet state of the primary donor of PSII. Triplet formation is potentially harmful because chlorophyll triplets can react with molecular oxygen to produce the reactive singlet oxygen (1O2). The yield of 1O2 is expected to be directly proportional to the triplet yield and the triplet yield of charge recombination can be lowered with a magnetic field of 100–300 mT. In this study, we illuminated intact pumpkin leaves with strong light in the presence and absence of a magnetic field and found that the magnetic field protects against photoinhibition of PSII. The result suggests that radical pair recombination is responsible for significant part of 1O2 production in the chloroplast. The magnetic field effect vanished if leaves were illuminated in the presence of lincomycin, an inhibitor of chloroplast protein synthesis, or if isolated thylakoid membranes were exposed to light. These data, in turn, indicate that 1O2 produced by the recombination of the primary charge pair is not directly involved in photoinactivation of PSII but instead damages PSII by inhibiting the repair of photoinhibited PSII. We also found that an Arabidopsis thaliana mutant lacking α‐tocopherol, a scavenger of 1O2, is more sensitive to photoinhibition than the wild‐type in the absence but not in the presence of lincomycin, confirming that the target of 1O2 is the repair mechanism. [ABSTRACT FROM AUTHOR]