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The natural, economic, and social attributes of mineral resources determine that the security of mineral resources involves numerous resource types, large spatial distribution, ultra-long industrial chains, huge industrial scale, spatial and temporal configurations, complex factors, and multiple levels; it is a complex and giant system with a large scale, multiple levels, and complex influencing factors. How to make this system operate efficiently and serve economic and social development is a complex scientific issue. This study puts forward a concept of giant system for mineral resource security by introducing the research idea of system science, depicts the structure and composition of the giant system, and reveals the driving mechanism of the giant system by natural resource, economic, social, and other factors. On this basis, a new research direction of system engineering of mineral resource security is established, which involves building a theoretical knowledge model for mineral resource security guarantee using a system thinking, constructing a simulation experiment system based on a big data platform, and actively promoting government decision-making and feedback. Furthermore, a major strategic idea of establishing an overall design department for mineral resource security is proposed. The research results have been applied to and effectively supported national resource security guarantee in China.

Basalts from the Late Carboniferous to Early Permian are extensively developed in the central Lhasa subterrane, southern Tibet. Studying the petrogenesis of these rocks may have implications for the late Paleozoic arc magmatism along the central Lhasa subterrane uncovering more of the evolution of the Sumdo Paleo‐Tethys Ocean and its dynamic mechanism. Basalt samples from the Luobadui Formation in the Leqingla area, NW of Linzhou City in the central Lhasa subterrane, southern Tibet exhibit arc‐like geochemical signatures in a subduction‐zone tectonic setting characterized by high Al2O3 and low TiO2 contents, fractionated REE patterns with low Nb/La ratios and high LREE concentrations, and negative HFSE anomalies. Based on their higher Th/Ce, Nb/Zr, and lower Ba/Th, Pb/Nd ratios, slightly negative to positive εNd(t) values, and the relatively high Sr‐Pb isotopic compositions, these samples were probably derived from partial melting of a depleted mantle source of garnet + spinel lherzolite, metasomatized by subducted sediments around 297 Ma. Modeling of the trace elements indicates that these basalts experienced fractional crystallization of olivine, clinopyroxene and minor plagioclase during magma ascent and eruption. It is proposed that these Late Carboniferous–Early Permian basalts are associated with the northward subduction of the Sumdo Paleo‐Tethys Ocean seafloor along the southern margin of the central Lhasa subterrane. [ABSTRACT FROM AUTHOR]

Antiferroelectric ceramics can realize ultra-high energy storage, which benefits from transformation between an antiferroelectric phase and a ferroelectric phase. Understanding the mechanism of such phase transition is the key point for building the structure-property correlation. Here, we report the observation of electric-induced devil's staircase in the course of antiferroelectric–ferroelectric phase transition in PbZrO3-based antiferroelectric ceramics by in situ transmission electron microscopy. The dynamic evolution as-revealed in both reciprocal- and real-space involves stepwise rather than monotonic increase in modulation periods along with simultaneous proliferation of nanodomains. Desynchrony of phase transition is observed for incommensurate domains with different initial modulation periods within a single antiferroelectric domain. Then, the synergistic effect of the devil's staircase and as small as possible the initial modulation period is believed to contribute to the superior energy-storage performance. These findings will be helpful for the development of theories for antiferroelectric–ferroelectric phase transition and the design of high-power antiferroelectric materials. [ABSTRACT FROM AUTHOR]