Three zinc–viologen materials exhibit reversible photochromism, photomodulated fluorescence and the capability as inkless and erasable print media.

The octahedron-shaped three-shell structure of the [(Ln14(H2O)W4(OH)O14)(WO4)4(GeW10O38)6]43− polyanion contains a W4 tetrahedron, a Ln14W4 tetrahedron and a Ge6W60 octahedron.

The construction of well-defined lanthanide complexes emitting in both the visible and near-infrared regions is of great importance due to their widespread applications in phosphors, light-emitting diodes, biosensors/probes, optical communications, etc. In comparison to the well-known mononuclear and dinuclear lanthanide complexes, multinuclear lanthanide supramolecular edifices with bright luminescence are still scarce. Herein, we report the coordination self-assembly of strongly luminescent lanthanide-organic tetrahedral Ln4L4 cages with a series of tris­(tridentate) ligands based on the triazole chelates. Among them, the new ligand L3 with triazole-pyridine-triazole (TPT) chelates manifests an excellent sensitization toward all of the lanthanide ions (Ln = Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb) that emit in both the visible and near-infrared regions, with a record luminescent quantum yield for Tb4(L3)4 (Φ = 82%) being obtained. In contrast, ligands with amido-pyridine-triazole (APT) or TPA chelates show much weaker sensitization ability. Energy levels for all ligands were measured, and TD-DFT calculations were employed to shed light on the sensitization mechanism. Finally, white-light emission systems formed by combining the desired luminescent compounds have been demonstrated. Our strongly luminescent LOPs provide new candidates for photochemical supramolecular devices.

Two organic–inorganic hybrid polyoxotungstogermanates are constructed from organic ligand chelated Fe–Dy heterometallic clusters and [B-α-GeW9O34]10− units with frequency dependent magnetic properties.

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This paper proposed a comprehensive control method for energy storage system (ESS) participating in primary frequency regulation (PFR). The integrated control strategy consists of PFR stage and "stage of charge" (SOC) recovery stage. In the PFR stage, the virtual droop control and virtual inertia control are combined and applied in the frequency deterioration phase to reduce the frequency deviation. The virtual negative inertia control coupled with virtual droop control is used in the frequency recovery phase to accelerate frequency recovery. In the SOC recovery stage, an adaptive SOC recovery control method is proposed. The SOC recovery control is performed while the frequency is within the dead zone, and the recovery power of ESS is based on the SOC to avoid overcharging and over-discharging. The proposed SOC recovery control can restore the SOC to a proper range which ensures the potential for ESS to participate in the next PFR process. It also reduces the number of SOC recovery starts compared with the fixed target SOC method and is beneficial to prolong the cycle life of ESS. Simulation outcomes demonstrate that the proposed comprehensive control method can efficiently enhance the frequency regulation performance and restore the SOC to the target range.

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