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The development of the sedimentary basin in the South Yellow Sea that lies between the Chinese mainland and the Korean Peninsula well documents the tectonic evolution of eastern China. However, the Moho morphology and its relationship with the basin in this area remain poorly understood. Here we used high‐resolution 2D seismic lines and well data to map the geometry, structure, and distribution of the sedimentary basin in the South Yellow Sea. Our results suggest that the South Yellow Sea Basin can be divided into two distinct depressions and three uplifts. The depressions consist of eight depositional sags that are largely controlled by ENE‐, EW‐, and WNW‐striking normal faults. The basin depth reaches 9,500 m in the depressions, but is only <2000 m in the uplift zones. Calculated using a gravity stripping method, the Moho depth varies between 27.4 and 31.5 km. The basin is isostatically compensated and the Moho morphology approximately mirrors that of the basin basement. The Moho lows correspond to the uplift zones and Moho highs correspond to the depression zones, with exception of a sag in the Northern Depression. This exception is caused by the presence of a geological body of high velocity and high density beneath the sag. This body is likely to represent high‐pressure metamorphic rock that initially formed during the collision between the Sino‐Korean and Yangtze cratons and are currently overlain by the sedimentary basin. Based on the stretching factors and strain rates of the South Yellow Sea Basin, we propose that development of the basin was primarily driven by the subduction and retreat of the Pacific Plate since the Late Cretaceous, combined by far‐field effects from the convergence between the Indian and Eurasian plates during the Cenozoic. [ABSTRACT FROM AUTHOR]

In this study, Cr3+‐doped and Mn4+‐Cr3+ co‐doped double perovskite fluoride phosphors K2LiGaF6 are prepared using a simple hydrothermal method. High‐efficiency near‐infrared (NIR) emission near 762 nm is obtained under blue‐light excitation, and the co‐doping effect of Mn4+ on the NIR luminescence properties of Cr3+ is studied. Compared with the Cr3+ single‐doped phosphor, Mn4+, and Cr3+ co‐doped K2LiGaF6 exhibit a sharp increase of 129% in NIR emission, an enhancement in the internal quantum efficiency from 82.5% to 90.0%, and an enhancement in the thermal stability at 425 K from 85.0% to 90.7%. The encapsulated NIR phosphor‐converted light‐emitting diode device at 300 mA exhibits a photoelectric conversion efficiency of 15.3%. These values exceed most previously reported results. This study provides a new approach for enhancing the luminescence properties of Cr3+‐doped fluoride NIR phosphors. [ABSTRACT FROM AUTHOR]

Coeval Neoproterozoic mafic dykes with a well‐constrained isotopic age of 925 Ma are distributed in the North China Craton (NCC) of China and São Francisco Craton (SFC) of Brazil. Several recent studies favor the hypothesis that these two cratons were connected during 925 Ma and constituted building cratons for the supercontinent Rodinia. However, the paleo‐positions of the two cratons in Rodinia have not yet been paleomagnetically resolved. This paper presents the paleomagnetic results of these dykes in both NCC and SFC. Detailed thermal and alternating‐field demagnetization revealed that these dykes record stable components of magnetization with unblocking temperatures below the Curie temperature of magnetite. Rock magnetic results and scanning electron microscope analysis further confirm that the major magnetic minerals in dyke samples are pseudo‐single domain titanomagnetites. The mean directions of the characteristic remanent magnetization (ChRM) of the dykes are distinct from those of rocks of different ages in the sampling localities, and are supported by positive baked contact tests, indicating primary remanent magnetization. The ChRM of the SFC dykes also exhibits dual polarity. Our results suggest that the NCC and SFC were in the moderate to high paleolatitudes of the Southern Hemisphere during approximately 925 Ma, suggesting a possible paleogeographic connection between the two cratons. A new paleogeographic reconstruction of both cratons during 925 Ma is proposed, which is supported by other geological evidence. Plain Language Summary: The formation and breakup of the supercontinent Rodinia have played crucial roles in the global tectonic evolution and paleoclimate changes during the Neoproterozoic which lasted from 1.0 billion to 541 million years ago. The exact configuration of the Rodinia remains debatable, including whether the North China Craton (NCC) and São Francisco Craton (SFC) were integral components of the Rodinia. In this paper, we present new results of an integrated investigation, including paleomagnetic and rock magnetic studies and scanning electron microscope analysis, on the well dated coeval 925 Ma mafic dykes in both NCC and SFC. The results of scanning electron microscope and magnetic measurements confirm the major magnetic minerals and the stability of characteristic remanence directions. The results imply that both NCC and SFC were located at moderate to high paleolatitudes of the Southern Hemisphere during approximately 925 Ma, suggesting the possibility of a paleogeographic connection between the two cratons in the Rodinia. The findings of this study help gain improved understanding of paleogeography of the early Earth. Key Points: Characteristic remanence for the 925 Ma dykes in North China Craton and São Francisco Craton is interpreted as primaryBoth cratons were located at moderate–high paleolatitudes, southwest of Rodinia's core at 925 Ma, suggesting a paleogeographic connectionThe possible paleogeographic connection between the two cratons is supported by new paleomagnetic and geological evidence [ABSTRACT FROM AUTHOR]

Fluoride phosphors as red components for warm white LEDs have attracted a tremendous amount of research attention. But these phosphors are extremely sensitive to moisture, which seriously limits their practical industrial applications. To tackle this problem, unlike all the straightforward preventive strategies, a reverse strategy "Good comes from bad" was successfully developed to treat the degraded K2SiF6 : Mn4+ (D‐KSFM) phosphor in the present study, which not only completely restores the luminescence properties, but also significantly enhances the moisture resistance at the same time. After treatment with an oxalic acid solution as restoration modifier, the emission intensity of the D‐KSFM phosphor can be restored to 103.7% of the original K2SiF6 : Mn4+ red phosphor (O‐KSFM), and the moisture resistance is remarkably improved. The restored K2SiF6 : Mn4+ (R‐KSFM) maintains approximately 62.3% of its initial relative emission intensity after immersing in deionized water for 300 min, while the reference commercial K2SiF6 : Mn4+ with a protective coating (C‐KSFM) is only 33.2%. As a proof of general applicability, this strategy was also conducted to K2TiF6 : Mn4+ phosphor, which is less moisture‐stable than K2SiF6 : Mn4+. The luminescence intensity of the degraded K2TiF6 : Mn4+ (D‐KTFM) phosphor can be restored to 162.6% of original level of the K2TiF6 : Mn4+ synthesized through a cation exchange approach without any treatment (O‐KTFM). The emission intensity of the restored K2TiF6 : Mn4+ (R‐KTFM) phosphor retains 62.8% of its initial emission intensity after soaking in deionized water for 300 min. Finally, the R‐KSFM phosphors were packaged into white light‐emitting diodes with blue InGaN chips and Y3Al5O12 : Ce3+ yellow phosphors. The WLEDs display excellent color rendition with higher color rendering index, lower color temperature (WLED‐II: Ra=83.6, R9=57.3, 3743 K, ηl=199.68 lm/W; WLED‐III: Ra=90.4, R9=94.2, 2892 K, ηl=183.3 1 m/W). The above results show that the reverse strategy can be applied in those phosphor materials with poor moisture resistance to restore luminescence properties and improve moisture resistance without excessively care about the deterioration during the production, storage and transportation. [ABSTRACT FROM AUTHOR]

Y1.94MAl4SiO12:0.06Ce3+ (M = Ba, Sr, Ca, Mg) phosphors were successfully prepared through a classic solid‐state reaction method. The crystal structures, photoluminescence spectra, quantum yields, and thermal stabilities of the phosphors were investigated in detail. The results indicate that all Y1.94MAl4SiO12:0.06Ce3+ phosphors maintain the crystal structure of garnets. The emission peaks of Y1.94MAl4SiO12:0.06Ce3+ (M = Ba, Sr, Ca, Mg) phosphors are located at 537, 538, 554, and 565 nm, respectively. A red‐shift trend of emission peak is observed with decreasing M radius, which can be ascribed to the increase in the crystal‐field splitting in the Ce3+ 5d level owing to the co‐doping of M2+−Si4+. Under 460 nm excitation, the luminescence quantum yields and thermal stabilities of the Y1.94MAl4SiO12:0.06Ce3+ phosphors decreased with the decrease of M radius. The IQE of the Y1.94BaAl4SiO12:0.06Ce3+ phosphor is 92.89%, and the resistance to thermal quenching is improved to be 93.32% at 150°C. In addition, the color shifts of Y1.94MAl4SiO12: 0.06Ce3+ phosphors with increasing temperature are all tiny, which also demonstrates good resistance to thermal quenching of luminescence. The linear shrinkage of Y1.94MAl4SiO12:0.06Ce3+ phosphors is significantly improved compared with that of YAG: Ce3+, which is expected to generate Y1.94MAl4SiO12:0.06Ce3+ transparent/translucent ceramics and fabricate high‐powder w‐LEDs for high‐quality solid‐state lighting in the future. [ABSTRACT FROM AUTHOR]

The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedimentary system, and metal ores and source rocks distributed widely during this period. Therefore, studying the Cryogenian stratigraphic framework and sedimentary basins is important to improve the stratigraphic resolution for metal mineral and hydrocarbon prospecting and exploration in China. This review paper firstly divides three tectonic‐stratigraphic regions in China in the Cryogenian, including the tectonic‐stratigraphic regions of Great South China, Xingmeng‐Tarim, and North China. Secondly, geochronologic data and geological records are combined to clearly depict the Cryogenian sedimentary sequence of continental blocks and micro‐continental blocks in different tectonic‐stratigraphic regions. The results were used to propose a new comparison scheme of stratigraphy for the Cryogenian in China. Finally, according to differences of sedimentary evolution and tectonic evolvement, sedimentary basins and their lithofacies paleogeography are identified and summarized, respectively. [ABSTRACT FROM AUTHOR]

The continent of China developed through the coalescence of three major cratons (North China, Tarim and Yangtze) and continental micro‐blocks through the processes of oceanic crust disappearance and acceretionary‐collision of continental crusts. The strata of the Chinese continental landmass are subdivided into 12 tectonic‐strata regions. Based on the composition of geological features among the three main cratons, continental micro‐blocks and other major global cratons, their affinities can be preliminarily deduced during the Tonian period, using evidence from sedimentary successions, paleobiogeography, tectonic and magmatic events. The Yangtze and Tarim cratons show that they have close affinities during the assembly‐dispersal milestone of the Rodinia Supercontinent. The sedimentary record and magmatic age populations in the blocks suggest that there was a widespread, intensive magmatic event that resulted from a subduction process during ∼1000–820 Ma, related to continental rifting around the Yangtze and Tarim cratons. However, they differ greatly from the North China Craton. The continental micro‐blocks in the Panthalassic Ocean could have some missing connection with the North China Craton that persisted until the Middle‐Late Devonian. In contrast, the Alxa Block showed a strong affinity with the Tarim Craton. The revised Tonian paleogeography of the Rodinia Supercontinent is a good demonstration of how to show the relationship between the main cratons and the continental micro‐blocks. [ABSTRACT FROM AUTHOR]