The photochemical microreactor has been a burgeoning field with important application in promoting photocatalytic reactions. The integration of light‐converting media and microflow chemistry renders new opportunity for efficient utilization of light and high conversion rate. However, the flexibility of emission light wavelength regulation and the universality of the microreactor remain significant problems to be solved. Here, a photochemical microreactor filled with fluorescent fluid is fabricated by a 3D printing technique. The light‐converting medium in the fluorescent fluid is used to collect and convert light, and then delivers light energy to the embedded continuous‐flow reaction channels to promote the chemical reaction process. With the merits of flowability, different light‐converting media can be replaced, making it a general tool for photocatalytic reactions in rapid screening, parameters optimization, and kinetic mechanism research.

In this work, a new method of direct laser writing patterned photonic crystal heterostructure on a glass surface is proposed. A multi-heterostructure photonic crystal (MHPC) is predeposited on the glass surface and then the laser spot is focused on it and moves according to the set program, leading to the formation of patterned MHPC. Scanning electron microscopy (SEM) and finite element simulation show that the patterning is caused by the local thermal annealing of the polymer colloidal spheres through the thermal conduction effect of the substrate on the laser energy. The patterned area presents a function of the water confinement effect and can be used as a highperformance droplet analysis chip. By integrating the patterned MHPC array and seven fluorescent dyes, nine metal ions can be successfully recognized and discriminated. This approach is quite facile and fast for designing colloidal photonic crystals with controllable patterns. Moreover, it is of considerable significance for the practical application of photonic crystal heterostructure in the detection, sensing, anti-counterfeiting, and display fields.

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Based on the panel data of environmental Non-Governmental Organizations (ENGOs) and air pollution in OECD countries, this paper uses econometric model to investigate the governance effect of ENGOs on air pollution. The results show that: ENGOs have a positive impact on the improvement of environmental quality, and the results are still valid after a series of robustness tests; Further mechanism analysis found that the environmental improvement by ENGOs is mainly achieved by increasing investment in environmental protection. This study provides empirical evidence for the effect of ENGOs on air pollution, and further provides ideas for environmental governance.