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• Radiation transfer in large angles of TM mode. • Dynamic control of TE mode by VO 2 gratings. • Wide-band controllable emission differences. • Temperature-controlled color displays. The phenomenon of controlling far-field thermal radiation with large-angle emission has gradually attracted attention, but it was previously only present in the TM mode. The ability to make the TE mode have a similar emission trend to the TM mode is important. By introducing a grating-like phase change material:vanadium dioxide (VO 2), the emitter has achieved wide-band controllable differences in TE emission rates between the two modes in the atmospheric window range (8–13 um). The range of variation in the emission rate is close to 0.9. Furthermore, temperature-controlled color displays at different angles have been added to the emitter, which makes it easier to judge the working state of the emitter visually. This adjustable broadband large-angle directional emitter makes angle-dependent thermal radiation control possible. It has potential application value in the fields of thermal camouflage, directional radiative cooling, solar cooling waste and heat recovery. [Display omitted] [ABSTRACT FROM AUTHOR]

Radiative cooling technology radiates heat into cold space through the atmospheric window without external energy. Integrating color display and radiative cooling is necessary to meet both aesthetic and practical requirements in real-life applications. In this study, we developed an efficient colored radiative cooler by depositing a cone emitter on an elliptical metal-insulator-metal (MIM) reflector. The upper emitter has an average emissivity of 96.62 % in the atmospheric window, while the lower part is tuned to achieve specific colors. Besides the tunability of geometry parameters, it is possible to produce diverse color display without re-modification of the structure by varying the polarization angle. Meanwhile, high emissivity can be achieved at different incident angles. Finally, the colored logo of Zhengzhou University (ZZU) is realized in our design with the polarization angles of 0° and 45° for comparison. Unlike conventional radiative coolers, our proposed cooler not only adjusts color display through geometry parameters or polarization angle, but also possesses a highly efficient cooling power. These advantages open up new avenues for energy saving, cooling, and color display. • A cone emitter on an elliptical MIM reflector has been designed to achieve radiative cooling and aesthetic performance. • A high emissivity of 96.62 % has been achieved in the first transparency window with the top SiO 2 cone. • A specific color can be flexibly tuned with the structural parameters and polarization angle. • Controllable emissivity and radiative cooling power are further realized with different incident angles. [ABSTRACT FROM AUTHOR]

Background The use of colors in visual displays can facilitate visual search and perception, but their use may not be effective without consideration of differences in the interpretation of their connoted meanings between individuals of different occupational backgrounds. Objective This study examined color-concept associations for Hong Kong Chinese students and white-collar workers, and then compared their associations with those of two other occupational groups to assess whether occupational background is related to color-concept associations. Method A questionnaire survey was used to examine color-concept associations among 100 university students and 100 white-collar workers in Hong Kong. The participants were presented with 16 safety-related concepts and were asked to choose one of 10 colors that best represented each concept. The associations reported by four groups with different occupations (the two groups in this study and the groups of managerial staff and steel workers examined in our previous study) were compared. A chi-square test was applied to determine whether significant color association(s) existed for each concept. Results Our results revealed that each concept was significantly associated with at least one color ( p < 0.01). The Hong Kong white-collar workers and managerial staff in mainland China both expressed the same color associations for 14 of the tested concepts, and differed only over which colors were associated with “strong,” and “radiation hazard.” These findings generally suggest that populations with similar occupations can have similar color perceptions. However, the students and the other three employee groups reported different color associations with the concepts “normal,” “off” and “potential hazard.” Conclusions Occupational background is associated with how color is interpreted for its connoted meaning. One should consider occupational background carefully when choosing colors in product designs, especially for safety. [ABSTRACT FROM AUTHOR]