Hebei Normal University

A novel zinc-based coordination polymer, namely [Zn(HDPNA)(2,2'-bipy)]_n (1, H₃DPNA = 2-(3,5-dicarboxylphenyl)nicotinic acid, 2,2'-bipy = 2,2'-bipyridine), was successfully constructed through a mixed-ligand strategy. Fluorescence analysis revealed that 1 displayed selective fluorescence enhancement exclusively towards Ag⁺ ions, with a detection limit of 9.73 × 10^-9 M, which may be due to π···Ag⁺···π interactions formed between Ag⁺ ions and the suitably arranged ligands in the polymer. Molecular docking results confirmed that such interactions enhance electron delocalization and inhibit non-radiative transitions. In addition, 1 exhibited highly selective luminescence quenching responses towards Cu²⁺ and Co²⁺ ions, with detection limits of 8.75 × 10^-9 M and 4.36 × 10^-9 M, respectively. The addition of excessive glutathione enabled 1 to display different 'on' and 'off' behaviors towards Cu²⁺ and Co²⁺ and thus allowed to assess even mixtures of these cations. With respect to the detection mechanism of 1 towards Cu²⁺ and Co²⁺, we suggest based on theoretical calculations that photoinduced electron transfer (PET) may lead to fluorescence quenching. Detection experiments under realistic conditions have proved that this new fluorescence sensor can be applied to the detection of Ag⁺, Cu²⁺ and Co²⁺ in real life samples, e.g. tap water. Coordination polymer 1 represents an efficient and multifunctional chemical sensor platform based on 'on-off' fluorescence detection and may provide guidance for the advanced development of multi-ions sensors based on coordination compounds.

Porous carbon materials have important applications in energy storage and conversion due to sufficient raw materials, adjustable pore structure and specific surface area. However, developing porous carbons with both a simple preparation process and excellent performance remain a significant challenge. Herein, we propose synthesizing S/O co-doped porous carbon (SOPC-3) by regulating the S/O ratio and introducing abundant adsorption sites. According to electrochemical tests, SOPC-3 has a high Na⁺ storage capacity of 396.7 mAh g^-1 at 1 A g^-1. After 3500 cycles, it maintains 192.7 mAh g^-1 at a current density of 10 A g^-1. Combined with theoretical calculations and material characterization analysis, the excellent performance is attributed to the fact that the S/O co-doping promotes the reversible adsorption-desorption process of Na⁺, and the rich pore structure provides more ion diffusion paths. Meanwhile, the prepared by K₂CO₃-assisted KOH activated asphalt (KAC) maintains a reversible capacity of 69.0 mAh g^-1 over 2400 cycles at a current density of 0.5 A g^-1. Finally, at the power density of 140 W kg^-1, the assembled sodium-ion hybrid capacitor (SOPC-3//KAC) demonstrates a high energy density of 104.2 Wh kg^-1. This work provides important theoretical guidance for the design of high-performance carbon-based energy storage materials.

The audiovisual bounce-inducing effect (ABE) is a phenomenon that the brain integrates spatial and temporal information from different sensory modalities of vision and hearing. At present, some researchers have conducted research on the individual differences of the ABE, but have not considered the factor of audiovisual stimulus intervals. This study investigated the neural mechanisms underlying the intra- and inter-individual differences in subjects' ABE at different audiovisual stimulus onset asynchronies (SOAs). This study adopted the experimental paradigm of Stream/Bounce illusion, in which visual and auditory stimuli were presented in 7 different SOAs. We recorded behavioral and EEG data during the experiment, compared and analyzed the amplitude differences of event-related potentials (ERPs), calculated statistical indicators, and studied the intra- and inter-individual differences of the ABE under different SOAs. The results show that in terms of the inter-individual differences in the ABE, the amplitude of N1 is more significant in the High ABE Group than the Low ABE Group at SOAs of "V100A" and "0". Individual ABE tendencies are also significantly correlated with N1 amplitude at the two SOAs. These results reveal the effect of stimuli interval on the processing of audiovisual stimuli, there is a complex interplay between the individual's sensory processing mechanisms and the specific temporal dynamics of audiovisual integration.