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Dynamic fluorescence patterns with variable output in response to external stimulus can make the current information storage technologies more flexible and intelligent. Yet it remains a great challenge to create such dynamic patterns because of the complicated synthesis process, high cost, limited stability, and biocompatibility of the functional fluorophores. Herein, a facile approach is presented for creating dynamic fluorescence patterns using the photodynamic surface chemistry based on disulfide bonds. By this method, high‐resolution (≈20 µm) multicolor dynamic fluorescence patterns that are low‐cost and dynamically rewritable can be easily fabricated using classical fluorophores such as fluorescein, rhodamine, and dansyl acid. Owing to the spatio‐temporal controllability of light, the fluorescence patterns can be partly or entirely erased/rewritten on demand, and complex gray‐level fluorescence images with increased information capacity can be easily generated. The obtained fluorescence patterns exhibit little changes after storing in air and solvent environments for 100 days, demonstrating their high stability. In addition, static patterns can also be created on the same disulfide surface using irreversible disulfide–ene chemistry, to selectively control the dynamicity of the generated fluorescence patterns. The authors show the successful application of this strategy on information protection and transformation.

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The four miniature heat pipes filled with DI water and SiO2-water nanofluids containing different volume concentrations (0.2%, 0.6% and 1.0%) are experimentally measured on the condition of air and water cooling. The wall temperature and the thermal resistance are investigated for three inclination angles. At the same of inlet heat water temperature in the heat system, it is observed that the total wall temperatures on the evaporator section are almost retaining constant by air cooling and the wall temperatures at the front end of the evaporator section are slightly reduced by water cooling. However, the wall temperatures at the condenser section using SiO2-water nanofluids are all higher than that for DI water on the two cooling conditions. As compared with the heat pipe using DI water, the decreasing of the thermal resistance in heat pipe using nanofluids is about 43.10%-74.46% by air cooling and 51.43%-72.22% by water cooling. These indicate that the utilization of SiO2-water nanofluids as working fluids enhances the performance of the miniature heat pipe. When the four miniature heat pipes are cut to examine at the end of the experiment, a thin coating on the surface of the screen mesh of the heat pipe using SiO2-water nanofluids is found. This may be one reason for reinforcing the heat transfer performance of the miniature heat pipe.

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