The South China Craton consists of the Yangtze and Cathaysia blocks that were welded together along the Jiangnan Fold Belt in the Neoproterozoic. The Neoproterozoic magmatism in the western and ...northern margins of the Yangtze Block is characterized by voluminous volcano-sedimentary strata, numerous felsic intrusions and many mafic-ultramafic plutons which provide a good opportunity to examine the geodynamics and tectonic evolution of the South China Craton during the assembly and breakup of Rodinia. Based on the geochronological and geochemical data, our study shows that the Neoproterozoic igneous rocks in the western and northern margins of the Yangtze Block were formed in subduction- and rift-related tectonic settings, respectively.
In the western margin of the Yangtze Block, the Neoproterozoic mafic and ultramafic rocks show arc-affinity trace elemental compositions that are indicative of mantle sources enriched by slab fluids. High-δ18O mafic rocks (850–780 Ma) were derived from mantle wedges that were modified by sediment melts, whereas low-δ18O mafic rocks (750–740 Ma) were formed by partial melting of mantle sources further enriched by altered oceanic crust melts. The widespread calc-alkaline I-type granitoids in this region, generated between 870 and 750 Ma, show negative to positive whole rock εNd (−4.9 to +4.8) and variable zircon εHf values (−1.9 to +10.6), similar to those of the contemporary mafic-ultramafic rocks, suggesting that they were produced by melting of the juvenile crust. The 780–750 Ma adakitic granitoids are characterized by high Sr/Y (19–318) and low Y (1.78–17.9 ppm) and have relatively constant εNd (−2.1 to +2.9) and εHf (+4.3 to +7.1) and mantle-like δ18O values (3.40‰ to 6.86‰), suggesting that they were partial melts of a subducted oceanic slab. These three types of igneous rocks demonstrate that the Neoproterozoic magmatism in the western margin of the Yangtze Block was controlled by a continuous subduction system.
However, Neoproterozoic magmatism in the South Qinling Belt at the northern margin of the Yangtze Block generated both arc- and rift-related igneous rocks. The arc-like mafic-ultramafic rocks are thought to have been derived from a subduction-modified lithospheric mantle source, whereas the MORB-affinity mafic rocks were probably sourced from an asthenosphere mantle. Associated Neoproterozoic granitoids were produced by melting of the juvenile mafic crust, except minor felsic rocks derived from the ancient basement. Widespread 800–700 Ma volcano-sedimentary sequences and 650 Ma mafic dike swarms suggest an extensional environment. Neoproterozoic magmatic zircons from felsic volcanic rocks and HP/UHP metamorphic rocks preserve low-δ18O values that were inherited from their protolith which underwent high temperature hydrothermal interaction in a rift setting. On the basis of these observations, the Neoproterozoic magmatism in the South Qinling Belt is proposed to have been controlled by a subduction-transform edge propagator (STEP) in relation to the continuous subduction system at the western margin of the Yangtze Block.
Abstract
Li-ion-conducting chloride solid electrolytes receive considerable attention due to their physicochemical characteristics such as high ionic conductivity, deformability and oxidative ...stability. However, the raw materials are expensive, and large-scale use of this class of inorganic superionic conductors seems unlikely. Here, a cost-effective chloride solid electrolyte, Li
2
ZrCl
6
, is reported. Its raw materials are several orders of magnitude cheaper than those for the state-of-the-art chloride solid electrolytes, but high ionic conductivity (0.81 mS cm
–1
at room temperature), deformability, and compatibility with 4V-class cathodes are still simultaneously achieved in Li
2
ZrCl
6
. Moreover, Li
2
ZrCl
6
demonstrates a humidity tolerance with no sign of moisture uptake or conductivity degradation after exposure to an atmosphere with 5% relative humidity. By combining Li
2
ZrCl
6
with the Li-In anode and the single-crystal LiNi
0.8
Mn
0.1
Co
0.1
O
2
cathode, we report a room-temperature all-solid-state cell with a stable specific capacity of about 150 mAh g
–1
for 200 cycles at 200 mA g
–1
.
Topological modes (TMs) are usually localized at defects or boundaries of a much larger topological lattice
. Recent studies of non-Hermitian band theories unveiled the non-Hermitian skin effect ...(NHSE), by which the bulk states collapse to the boundary as skin modes
. Here we explore the NHSE to reshape the wavefunctions of TMs by delocalizing them from the boundary. At a critical non-Hermitian parameter, the in-gap TMs even become completely extended in the entire bulk lattice, forming an 'extended mode outside of a continuum'. These extended modes are still protected by bulk-band topology, making them robust against local disorders. The morphing of TM wavefunction is experimentally realized in active mechanical lattices in both one-dimensional and two-dimensional topological lattices, as well as in a higher-order topological lattice. Furthermore, by the judicious engineering of the non-Hermiticity distribution, the TMs can deform into a diversity of shapes. Our findings not only broaden and deepen the current understanding of the TMs and the NHSE but also open new grounds for topological applications.
Although pyroptosis is critical for macrophages against pathogen infection, its role and mechanism in cancer cells remains unclear. PD-L1 has been detected in the nucleus, with unknown function. Here ...we show that PD-L1 switches TNFα-induced apoptosis to pyroptosis in cancer cells, resulting in tumour necrosis. Under hypoxia, p-Stat3 physically interacts with PD-L1 and facilitates its nuclear translocation, enhancing the transcription of the gasdermin C (GSDMC) gene. GSDMC is specifically cleaved by caspase-8 with TNFα treatment, generating a GSDMC N-terminal domain that forms pores on the cell membrane and induces pyroptosis. Nuclear PD-L1, caspase-8 and GSDMC are required for macrophage-derived TNFα-induced tumour necrosis in vivo. Moreover, high expression of GSDMC correlates with poor survival. Antibiotic chemotherapy drugs induce pyroptosis in breast cancer. These findings identify a non-immune checkpoint function of PD-L1 and provide an unexpected concept that GSDMC/caspase-8 mediates a non-canonical pyroptosis pathway in cancer cells, causing tumour necrosis.
We pave the way for future gravitational-wave detection experiments, such as the big bang observer and DECIGO, to constraint dark sectors made of SU(N) Yang-Mills confined theories. We go beyond the ...state-of-the-art by combining first principle lattice results and effective field theory approaches to infer essential information about the nonperturbative dark deconfinement phase transition driving the generation of gravitational-waves in the early Universe, such as the order, duration and energy budget of the phase transition which are essential in establishing the strength of the resulting gravitational-wave signal.
Photoelectrochemical (PEC) water splitting is an attractive strategy for the large‐scale production of renewable hydrogen from water. Developing cost‐effective, active and stable semiconducting ...photoelectrodes is extremely important for achieving PEC water splitting with high solar‐to‐hydrogen efficiency. Perovskite oxides as a large family of semiconducting metal oxides are extensively investigated as electrodes in PEC water splitting owing to their abundance, high (photo)electrochemical stability, compositional and structural flexibility allowing the achievement of high electrocatalytic activity, superior sunlight absorption capability and precise control and tuning of band gaps and band edges. In this review, the research progress in the design, development, and application of perovskite oxides in PEC water splitting is summarized, with a special emphasis placed on understanding the relationship between the composition/structure and (photo)electrochemical activity.
Among the most important classes of materials for the application as electrodes for photoelectrochemical (PEC) water splitting are perovskite oxides. In this Review, recent progress about the development of high‐performance perovskite oxide based electrodes for PEC water splitting is discussed. The design strategies, challenges and perspectives of perovskite oxides as electrodes for PEC water splitting are also presented.
Ratios of specific carbon (C), nitrogen (N) and phosphorus (P) acquisition activities converged on 1:1:1 at a global scale and in tropical ecosystems. It is less clear if this pattern can be applied ...in temperate grasslands. The questions of whether the pattern remains stable across different soil depths and what the relative contributions are from the influence of climatic, edaphic abiotic and biotic factors on soil extracellular enzyme activity (EEA) stoichiometry remain uncertain. We measured potential activities of one C-acquiring enzyme (β-1, 4-glucosidase), two N-acquiring enzymes (β-N-acetylglucosaminidase and leucine aminopeptidase) and one organic P-acquiring enzyme (acid phosphatase) and major influential factors along a climatic transect in temperate grasslands of northern China during the growing season of 2013. We found lower enzyme C: N (0.47) and C: P (0.18) ratios and a higher enzyme N: P activity ratio (0.40) in 0–20 cm soil depth in temperate grasslands than in tropical soils (C: N, 1.83; C:P, 0.21; N: P, 0.13). The enzyme C: N and C: P ratios decreased with soil depth except for the enzyme C: N ratio in desert steppes. However, there were no significant differences in enzyme N: P ratio with soil depth. Among all the factors, soil total C, N and P contents accounted for the most variation in soil EEA and ecoenzymatic stoichiometry in 0–10 cm surface soil, which implied that soil EEA stoichiometry was largely controlled by soil nutrient stoichiometry. Moreover, edaphic factors had less influence on soil EEA stoichiometry in subsoil than in surface soil and edaphic abiotic factors had a larger effect on soil EEA stoichiometry than climatic and biotic factors. Our results suggest that soil extracellular enzyme activity ratios were not in homeostasis but resource dependent on soil and microbial biomass stoichiometry.
•Ratios of log-transformed C-, N- and P-acquiring enzymes were 1:1.2:1.4.•Enzyme C:N and C:P ratios declined with soil depth, while enzyme N:P ratio remained stable.•Soil extracellular enzyme activity ratio was not in homeostasis but resource dependent on soil and microbial biomass stoichiometry.
Their chemical stability, high specific surface area, and electric conductivity enable porous carbon materials to be the most commonly used electrode materials for electrochemical capacitors (also ...known as supercapacitors). To further increase the energy and power density, engineering of the pore structures with a higher electrochemical accessible surface area, faster ion‐transport path and a more‐robust interface with the electrolyte is widely investigated. Compared with traditional porous carbons, two‐dimensional (2D) porous carbon sheets with an interlinked hierarchical porous structure are a good candidate for supercapacitors due to their advantages in high aspect ratio for electrode packing and electron transport, hierarchical pore structures for ion transport, and short ion‐transport length. Recent progress on the synthesis of 2D porous carbons is reported here, along with the improved electrochemical behavior due to enhanced ion transport. Challenges for the controlled preparation of 2D porous carbons with desired properties are also discussed; these require precise tuning of the hierarchical structure and a clarification of the formation mechanisms.
Two‐dimensional (2D) porous carbon sheets, which can be synthesized by templating approaches, biomass carbonization, biomass carbonization–activation, in situ activation, etc, are good candidates for supercapacitors due to their advantages in their short ion‐transport length and high aspect ratio for electrode packing and electron transport.
To enable large-scale and ubiquitous automotive network access, traditional vehicle-to-everything (V2X) technologies are evolving to the Internet of Vehicles (IoV) for increasing demands on emerging ...advanced vehicular applications, such as intelligent transportation systems (ITS) and autonomous vehicles. In recent years, IoV technologies have been developed and achieved significant progress. However, it is still unclear what is the evolution path and what are the challenges and opportunities brought by IoV. For the aforementioned considerations, this article provides a thorough survey on the historical process and status quo of V2X technologies, as well as demonstration of emerging technology developing directions toward IoV. We first review the early stage when the dedicated short-range communications (DSRC) was issued as an important initial beginning and compared the cellular V2X with IEEE 802.11 V2X communications in terms of both the pros and cons. In addition, considering the advent of big data and cloud-edge regime, we highlight the key technical challenges and pinpoint the opportunities toward the big data-driven IoV and cloud-based IoV, respectively. We believe our comprehensive survey on evolutionary V2X technologies toward IoV can provide beneficial insights and inspirations for both academia and the IoV industry.
Traditional coupling of ligands for gold wet etching makes large-scale applications problematic. Deep eutectic solvents (DESs) are a new class of environment-friendly solvents, which could possibly ...overcome the shortcomings. In this work, the effect of water content on the Au anodic process in DES ethaline was investigated by combining linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). Meanwhile, we employed atomic force microscopy (AFM) to image the evolution of the surface morphology of the Au electrode during its dissolution and passivation process. The obtained AFM data help to explain the observations about the effect of water content on the Au anodic process from the microscopic perspective. High water contents make the occurrence of anodic dissolution of gold at higher potential, but enhances the rate of the electron transfer and gold dissolution. AFM results reveal the occurrence of massive exfoliation, which confirms that the gold dissolution reaction is more violent in ethaline with higher water contents. In addition, AFM results illustrate that the passive film and its average roughness could be tailored by changing the water content of ethaline.
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