The Mogou syenite intruded into the Mesoproterozoic Xiong'er Group is the main lithostratigraphic unit, along the southern margin of the North China Craton (NCC). This paper reports zircon LA-ICP-MS data, whole-rock major and trace element compositions of late Triassic magmatic rocks in the Mogou syenite, in order to constrain the formation age of the Mogou syenite, research the origin and evolution of the magma and analyse the geodynamic setting of the Qinling Orogen (QO) in Late Triassic. These rocks consist of medium-to coarse-grained syenite and fine-grained quartz syenite. Zircon U-Pb dating yields a crystallization age of 226.5±2.7 Ma. The syenites are characterized by high SiO 2 (63.49-72.17%), alkali (K 2 O+Na 2 O of 11.18-15.38%) and potassium (K 2 O/Na 2 O of 2.88-28.11), are peralkaline or metaluminous (molar A/CNK of 0.87-1.02) and belong to shoshonite series. The syenites have ΣREE of 33.01-191.30 ppm, LREE/HREE of 14-20, (La/Yb) N of 11-24, with LREE-rich distribution pattern and obvious differentiation between HREE and LREE. Eu anomalies are positive for the medium-to coarse-grained syenite and weakly negative for the fine-grained quartz syenite. In addition, the syenites are enriched in large-ion lithophile elements (Ba, K, Sr, and Pb) but depleted in high strength field elements (Ti, Ta, Nb, Zr, and Hf), and have high differentiation indices of 91.69-97.06. These geochemical features indicate that the primary magma of the Mogou syenite most likely originated from a mantle source with minor crustal component, and underwent a fractional crystallization process during its emplacement. The late Triassic A-type Moguo syenite along the southern margin of the NCC was generated in the late stage of the syn-collision event of QO, recording a transition period from compression to extension at around 227 Ma.

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High‐capacity silicon has been regarded as one of the most promising anodes for high‐energy lithium‐ion batteries. However, it suffers from severe volume expansion, particle pulverization, and repeated solid electrolyte interphase (SEI) growth, which leads to rapid electrochemical failure, while the particle size also plays key role here and its effects remain elusive. In this paper, through multiple‐physical, chemical, and synchrotron‐based characterizations, the evolutions of the composition, structure, morphology, and surface chemistry of silicon anodes with the particle size ranging from 50 to 5 µm upon cycling are benchmarked, which greatly link to their electrochemical failure discrepancies. It is found that the nano‐ and micro‐silicon anodes undergo similar crystal to amorphous phase transition, but quite different composition transition upon de‐/lithiation; at the same time, the nano‐ and 1 µm‐silicon samples present obviously different mechanochemical behaviors from the 5 µm‐silicon sample, such as electrode crack, particle pulverization/crack as well as volume expansion; in addition, the micro‐silicon samples possess much thinner SEI layer than the nano‐silicon samples upon cycling, and also differences in SEI compositions. It is hoped this comprehensive study and understanding should offer critical insights into the exclusive and customized modification strategies to diverse silicon anodes ranging from nano to microscale.