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Denitrification-induced nitrogen (N) losses from croplands may be greatly increased by intensive fertilization. However, the accurate quantification of these losses is still challenging due to insufficient available in situ measurements of soil dinitrogen (N2) emissions. We carried out two one-week experiments in a maize–wheat cropping system with calcareous soil using the 15N gas-flux (15NGF) method to measure in situ N2 fluxes following urea application. Applications of 15N-labeled urea (99 atom%, 130–150 kg N ha−1) were followed by irrigation on the 1st, 3rd, and 5th days after fertilization (DAF 1, 3, and 5, respectively). The detection limits of the soil N2 fluxes were 163–1 565, 81–485, and 54–281 μg N m−2 h−1 for the two-, four-, and six-hour static chamber enclosures, respectively. The N2 fluxes measured in 120 cases varied between 159 and 2 943 (811 on average) μg N m−2 h−1, which were higher than the detection limits, with the exception of only two cases. The N2 fluxes at DAF 3 were significantly higher (by nearly 80% (P

Aggregation-induced electrochemiluminescence (AIECL) technology has aroused widespread interest due to the significant improve in ECL response by solving the problems of aggregation-caused quenching and poor water solubility of the luminophore. However, the existing AIECL emitters still suffer from low ECL efficiency, additional coreactants and complex synthesis steps, which greatly limit their applications. Herein, luminol, as a kind of AIE molecule, was assembled with Zn2+ nodes to obtain a novel microflower-like Zinc-luminol metal-organic gel (Zn-MOG) by one-step method. In the light of the strong affinity of N atoms in luminol ligand to Zn2+, Zn-MOG with vigorous viscosity and stability can be formed immediately after vortex oscillation, overcoming the main difficulties of the complicated synthesis steps and poor film-forming performance encountered in current AIECL materials. Impressively, an AIECL resonance energy transfer (RET) biosensor was constructed using Zn-MOG as a donor and Alexa Fluor 430 as an acceptor in combination with DNA-Fuel-driven target recycling amplification for the ultrasensitive detection of PiRNA-823. The fabricated biosensor exhibited a wide linear relationship in the range of 100 aM to 100 pM and a detection limit as low as 60.0 aM. This work is the first to realize the construction of ECL emitters using the AIE effect of luminol, which provides inspiration for the design of AIECL systems without adding coreactants. [ABSTRACT FROM AUTHOR]