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Protein characterization highly depends on its operating conditions, where native or often referred as non-denaturing options will greatly facilitate the collection of more biologically meaningful information. Native mass spectrometry (MS) is such a technique that enables protein analysis under non-denaturing conditions with an affordable time and sample cost. The indispensable roles of native MS-based strategies in the deep dissection of protein conformations, non-covalent interactions, and self-assembly stoichiometry have been seen in past decade, which suggest that native MS has increasingly grown to be a ground technique for the structural biology realm. In this review, we firstly introduced the current method development for protein extraction compatible with native MS experiments, ranging from traditional methods to in situ extraction means, which is key to achieve biologically meaningful native MS results. Then, we focused on the most recent advancements in the native MS-compatible ion source and novel regimes for protein conformational interpretation. Specifically, except the most frequently used nanoelectrospray ion source for native MS, we also listed a variety of emerging ionization regimes including nano-desorption electrospray ionization, submicron emitter tip electrospray, induced nanoelectrospray ionization, step-voltage nanoelectrospray ionization. For protein structural analysis, native MS relies on both charge state distribution and conformational interrogation tool, e.g. ion mobility spectrometry. The structural information can be further enriched when coupled to collision-induced unfolding technique, which was also discussed with most recent developments in data acquisition and visualization methods. Current challenges and potential solutions facing native MS realm in terms of both sampling methods and structural resolution were tentatively discussed.

The Jiamusi Block is an important tectonic unit in the Chinese segment of the CAOB. Its eastern margin became an active continental margin in the period of Late Carboniferous. However, the tectonic affinity of this section has not been resolved yet. The Early Permian andesites within the Erlongshan Formation in the eastern Jiamusi Block provide a critical record for the active continental margin setting. Precise LA‐ICP‐MS U–Pb zircon dating on four andesite samples gave ages of 280 ± 3 Ma, 282 ± 3 Ma, 286 ± 4, and 284 ± 2 Ma, respectively, defining an Early Permian age for the crystallization of the andesites. The andesites have medium‐K and calc‐alkaline compositions, with variable SiO2 (54.70–57.46 wt%), TiO2 (0.87–1.12 wt%), TFe2O3 (6.52–8.13 wt%), MgO (2.62–3.33 wt%), Al2O3 (15.96–17.83 wt%), Na2O (3.28–4.10 wt%), and K2O (1.16–1.95 wt%) contents. They are relatively enriched in LREEs ((La/Yb)N = 5.0–7.1) and LILEs (e.g., Ba, Th, Sr, and U), deleted in HREEs and HFSEs (e.g., Nb, Ta, Zr, and Y) and have weak or no Eu anomalies (Eu/Eu* = 0.87–1.02). These geochemical features indicate that the andesites within the Erlongshan Formation originated from an active continental margin setting, and their magma source was produced by partial melting of a mantle material that had been metasomatized by subduction‐related melts and subsequently underwent the removal of mafic minerals and accumulation of plagioclase. Integrated with previous studies on the igneous and sedimentary rocks, we thus propose that the Jiamusi Block was in an active continental margin setting in the period of the Late Carboniferous to Early Permian (310–280 Ma), and it is more likely related to the subduction of the Mongol‐Okhotsk Ocean. [ABSTRACT FROM AUTHOR]

• Devonian Heitai Form. formed in a passive continental margin setting. • Early Permian Zhenzishan Form. formed in an active continental margin setting. • The transition from a passive to an active continental margin in the Jiamusi Block occurred 380–310Ma. The eastern margin of the Jiamusi Block records the tectonic transition from a passive to an active continental margin during the Late Paleozoic- Early Mesozoic. Late Paleozoic sedimentary rocks from the Heitai and Zhenzishan formations along the eastern margin of the Jiamusi Block are a key to resolving these events. Major and trace element data (including REE) for 18 samples from late Paleozoic sedimentary rocks, with the characteristics of high SiO 2 , Al 2 O 3, Na 2 O and K 2 O, low CaO, MgO and TiO 2 , enrichment in LREE and LILE, depletion in HFSE, and negative Eu anomalies, were plotted on various discrimination diagrams, indicating that the Heitai Formation formed in a passive continental margin setting, whereas the Zhenzishan Formation formed in an active continental margin setting. LA-ICPMS U-Pb dating of detrital zircon from two samples of the Heitai Formation and two samples from the Zhenzishan Formation indicates a range in age from 2735 ± 19 to 308 ± 3 Ma, showing similar populations to the Jiamusi Block. These detrital zircons not only indicate that the sedimentary material was derived from the Jiamusi Block, but also limit the depositional ages of the Heitai and Zhenzishan formations. The youngest zircon population of 374–384 Ma, with a peak at 382 Ma, from the Heitai Formation, together with evidence from paleontological studies, indicates the depositionol age of the Heitai Formation is Devonian (Givetian- Famennian), whereas the 308–318 Ma population, with a peak at 315 Ma, from the Zhenzishan Formation indicates that the depositionol age was late Carboniferous (post- Moscovian). This indicates that the transition from a passive to an active continental margin in the Jiamusi Block occurred between the Late Devonian and the late Carboniferous (380-310Ma) and was more likely related to the Mongol-Okhotsk oceanic subduction-accretion or Panthalassa Ocean, and not to the Paleo-Pacific Ocean or to the Paleo-Asian Ocean as previous considered. [ABSTRACT FROM AUTHOR]

The time frame and detailed tectonic processes during the transition from the Paleo-Asian Ocean to the Paleo-Pacific Ocean regimes have long been controversial. The Jiamusi Block, which is located in the eastern margin of the Eurasia, is a transitional zone between the Paleo-Asian Ocean and the Paleo-Pacific Ocean regimes. The Jiamusi Block has been considered to be the last unit collaged to the Central Asian Orogenic Belt (CAOB) but also influenced by subsequent westward subduction and accretion of the Paleo-Pacific plate. Abundant geological units in the Jiamusi Block provide key insights into the final amalgamation of the CAOB and the onset of the Paleo-Pacific Ocean regime. This paper presents a review on the tectonic affinity and origin linkage of the Jiamusi Block based on detailed characterization of both the granulite facies basement and the Phanerozoic sedimentary cover, as well as the surrounding Mesozoic accretionary complexes. From these analyses, we develop an integral tectonic model for the Jiamusi Block aiming to better constraining the evolution history from the final amalgamation of the eastern CAOB to the onset of the Paleo-Pacific Ocean regime. We found that the tectonic history of the Jiamusi Block can be divided into at least four stages: (1) prior to the Early Paleozoic, the Jiamusi Block was conterminous with the other mirco-continents in NE China as a large combined block, which originated from the Sayang–Baikal orogenic belt within the Siberia Craton and experienced the Pan-African metamorphism (ca. 500 Ma); (2) along the tectonic evolution of the CAOB, those blocks in NE China drifted south to the eastern CAOB in some time after ca. 500 Ma; (3) during the Late Paleozoic, the subduction of the Mongol-Okhotsk Ocean or the Panthalassa induced back-arc extension and eventually the opening of the Heilongjiang Ocean, which ripped off the Jiamusi Block and drove it eastward away from the CAOB; (4) during the period from the Late Triassic to the Early Jurassic, following the closure of the Heilongjiang Ocean and the subduction of the Paleo-Pacific Ocean in the east, the Jiamusi Block was reunited with the contiguous CAOB, marking the final amalgamation of the CAOB and tectonic shift to a dominance by the Paleo-Pacific Ocean tectonic regime in the region. • Jiamusi Block is a hinge of tectonic transition between the Paleo-Asian Ocean and the Paleo-Pacific Ocean regimes. • Jiamusi Block together with the other parts of NE China was more likely originated from the Sayang–Baikal orogenic belt. • Jiamusi Block experienced eastward rift away during the Early Permian and reunion to the CAOB during the Late Triassic. [ABSTRACT FROM AUTHOR]

Taking Sihe Mine for background, according to additional hydrogeological exploration, the water resistance properties study about Fengfeng Group was done to prove the existence of relative aquifuge. At last, numerical simulation by FLAC3D was done when relative aquifuge exists to prove that the mining condition in deep part resource with water pressure gets clear improvement. So one of the key factors to do research in this condition is to find out whether the top part of Ordovician gets enough water resistance. [ABSTRACT FROM AUTHOR]