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The synthesis and hydrogen-storage properties of the mixed alkali metal and alkaline-earth metal borohydride are systematically investigated. It is found that mechanical milling a mixture of LiBH4 and CaCl2 with molar ratio of 3:1 in tetrahydrofuran (THF) forms a new LiBH4·Ca(BH4)2·2THF compound. Thermal analysis indicates that the decomposition process of the new compound involves four steps: (1) LiBH4·Ca(BH4)2·2THF decomposes first into high temperature phase of LiBH4, CaB6, and an intermediate phase Ca–B–H–Cl hydride and synchronously releases a large number of H2 and THF gas together with less B2H6; (2) the eutectic melting of LiBH4 and Ca–B–H–Cl hydride; (3) Ca–B–H–Cl hydride decomposes into CaHCl, CaB6, and a little H2; (4) LiBH4 reacts with CaHCl, generating H2, CaH2, CaB6, LiH, and LiCl. The first dehydrogenation step starts at ca. 70 °C, which is much lower than that of the pristine LiBH4 and Ca(BH4)2. According to Kissenger’s equation, the activation energies of the different dehydrogenation steps are respectively 291.95, 132.06, and 117.13 kJ/mol, except the second decomposition step. Moreover, this new compound LiBH4·Ca(BH4)2·2THF is proved to be partially reversible, which can release 5.63 wt % hydrogen in the second rehydrogenation/dehydrogenation cycle.

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Horseshoe crabs are an ancient group of marine arthropods. The Chinese horseshoe crab (Tachypleus tridentatus) is the largest among the four extant species. Tachypleus tridentatus is regarded as the indicator species of estuarine ecosystems. Meanwhile, its blood is used to manufacture biomedical testing kits, i.e., Tachypleus amebocyte lysate. The geographic distribution of T. tridentatus is constrained to the western Pacific Ocean, ranging from the Seto Inland Sea of Japan southwards to the North Jawa waters. A high historical population size of T. tridentatus was recorded in eastern China and southern Japan. Tachypleus tridentatus population decline has become apparent since the 1950s, and the species has been upgraded to "Endangered (EN)" under the IUCN Red List in 2019, depicting its global declining trend. Habitat destruction and overfishing are identified as the primary threats. We reexamined current conservation measures targeting T. tridentatus, including marine protected area establishment, captive breeding and restocking, and awareness programs and regulations. We provide recommendations to enhance the conservation and management of global T. tridentatus populations through: (1) expediting population baseline data collection; 综述(2) developing standards for population/habitat monitoring; and (3) establishing scientifically sound restocking programs.