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Two severe dust storm (DS) events (15–17 March and 28–29 March) hit northern China in 2021 consecutively. The lower atmospheric vertical dynamic and thermal structures during the two cases were compared using the ground-based sensor data from the microwave radiometer and radar wind profiler, combined with the environmental and meteorological observations data in Jinan, China. It was found that both cases occurred under the background of cold vortexes over northeastern China. The dust was transported through the cold air on the northwest route. During the dust period, 2–3 km was the west or northwest airflow, and below 2 km was the northeast wind. The variation in the dynamic structure determined the duration of the DS. During the DS maintenance phase, the vertical wind shear (VWS) below 3 km measured approximately 10 m∙(s∙km)−1. The increased VWS during the dust intrusion period facilitated the transportation of dust. In contrast, the more significant VWS was not conducive to the maintenance of DS, and the shift to south wind control in the upper middle layer indicated the weakening of DS. In both cases, we observed a cliff-like decrease in relative humidity as a prominent indicator of dust outbreaks, occurring approximately 2–5 h beforehand. The diurnal difference between the vertical temperature and relative humidity during the dust maintenance period was found to be insignificant. [ABSTRACT FROM AUTHOR]

Recycling cathode materials from spent lithium‐ion batteries (LIBs) is critical to a sustainable society as it will relief valuable but scarce recourse crises and reduce environment burdens simultaneously. Different from conventional hydrometallurgical and pyrometallurgical recycling methods, direct regeneration relies on non‐destructive cathode‐to‐cathode mode, and therefore, more time and energy‐saving along with an increased economic return and reduced CO2 footprint. This review retrospects the history of direct regeneration and discusses state‐of‐the‐art development. The reported methods, including high‐temperature solid‐state, hydrothermal/ionothermal, molten salt thermochemistry, and electrochemical method, are comparatively introduced, targeting at illustrating their underlying regeneration mechanism and applicability. Further, representative repairing and upcycling studies on wide‐applied cathodes, including LiCoO2 (LCO), ternary oxides, LiFePO4 (LFP), and LiMn2O4 (LMO), are presented, with an emphasis on milestone cases. Despite these achievements, there remain several critical issues that shall be addressed before the commercialization of the mentioned direct regeneration methods. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new beryllium borate SrBeB2O5 was synthesized. [•] A layered structure (BeB2O5)∞ was formed by BO3 triangles and B/BeO4 tetrahedrons. [•] SrBeB2O5 has a very wide transparency range of wavelengths from 200nm to 1800nm. [•] A-site ions impact greatly on the structures of beryllium borates. [ABSTRACT FROM AUTHOR]

Highlights: [•] New borate–malate crystals NaB(DL-C4H4O5)2 and CsB(DL-C4H4O5)2⋅H2O have been grown. [•] They display diverse framework geometries attributable to the size of the cations. [•] NaB(DL-C4H4O5)2 crystallizes in the noncentrosymmetric monoclinic space group P2. [•] Both crystals have absorption edges about 220nm in the UV region. [•] NaB(DL-C4H4O5)2 exhibits a NLO efficiency of 2times that of KDP (KH2PO4) standard. [ABSTRACT FROM AUTHOR]

Abstract: A novel fluorine beryllium borate crystal Sr0.23Ca0.77Na2Be2B2O6F2 has been grown by high temperature solution method from its self-flux system for the first time. Crystal structure of this compound was determined by single crystal X-ray diffraction. It crystallizes in the trigonal space group (No. 148) with lattice parameters a=4.6608(6) Å, c= 27.516(5) Å, Z=3, V= 517.65(13) Å3. The crystal displays a sandwich-like layered configuration along c axis with the infinite (Be6B6O12F3)∞ non-bonding double layer formed by two (Be3B3O6F3)∞ single layers in the a-b plane. The single layer was composed of BO3 triangle and BeO3F tetrahedron, both of which are the most favorable anionic groups in deep ultraviolet (UV) region. The structural relationship between the title compound and related fluorine beryllium borate was discussed. Optical transmittance spectrum reveals this compound has a very wide transmission range (190nm – 8μm). The IR spectrum and thermal behavior of Sr0.23Ca0.77Na2Be2B2O6F2 were also reported. [Copyright &y& Elsevier]