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The spontaneous parasitic reactions (hydrogen evolution, dendrite growth, etc.) of Zn metal hinder the commercial application of aqueous zinc ion batteries. Herein, a highly adhesive zinc-ion conductive buffer polymer layer is constructed using polyvinyl formal (PVF) to prevent these parasitic reactions to enhance the reversibility of Zn deposition. This dense artificial buffer layer can not only effectively isolate the direct contact between the anode and the electrolyte, but also accommodate volume expansion during Zn plating/stripping and guide the process of Zn nucleation. Specifically, this PVF layer increases the nucleation overpotential and promotes Zn2+three-dimensional diffusion process to homogenize the Zn2+flux underneath the layer. Hence, the PVF@Zn exhibits no dendrites and high cycling stability with a lifespan of 5200 h, which is a 35-fold enhancement compared with Zn, and can even run at an ultrahigh current density of 40.0 mA cm−2. Moreover, the PVF@Zn∥Na2V6O16full cell maintains a specific capacity of 172.4 mA h g−1(2400 cycles at 1.0 A g−1). This proposed strategy provides a practical insight into designing an excellent-performance Zn anode by eliminating the parasitic reactions and modulating the nucleation of Zn deposition.

Abstract: During the past ten years, various types of HP-UHP metamorphic rocks have been discovered in the South Altyn Tagh, the North Qaidam and the North Qinling (秦岭) in the West and Middle Central China orogen. The UHP rocks, as lentoid bodies in regional gneisses, include eclogite (garnet-bearing pyroxenite), garnet peridotite and various pelitic or felsic gneisses. There are many records of minerals and microstructures of exsolution indicate the UHP metamorphism, such as coesite (or its pseudomorph), diamond, exsolution of clinopyroxene/amphibole/+rutile or rutile+quartz+apatite in garnet, exsolution of quartz in omphacite and exsolution of kyanite+spinel in precursor stishovite. The discovery of microstructure evidence for the presence of precursor stishovite in typical Alrich gneiss from the South Altyn Tagh reveals continental subduction and exhumation to and from a depth of more than 350 km. It is the petrological record of the deepest subduction and exhumation of continental rock in the world. The in situ zircon U-Pb dating using LA-ICP-MS or SHRIMP methods shows that the metamorphic ages of the HP-UHP rocks in the South Altyn Tagh, the North Qaidam and the North Qinling are 475–509, 420–457, and 485–514 Ma, respectively. The metamorphic ages of HP-UHP rocks in the North Qaidam are 20–80 Ma younger than those in the South Altyn Tagh and the North Qinling, and the metamorphic ages do not systematically increase or decrease from the South Altyn Tagh through the North Qaidam to the North Qinling. The absence of time transgressive variety of the metamorphism in the three regions does not support the hypothesis that the HP-UHP rocks in these regions form the same HP-UHP metamorphic zone. And the HP-UHP rocks in these regions can not be simply correlated to the collision between the North China plate and the South China plate. At present, the study of the HP-UHP rocks in the West and Middle Central China orogen faces several key issues or challenges, such as: (1) the continental subduction to the mantle depth of stishovite stability field (>9 GPa) is occasional or universal; (2) the mechanism of exhumation for the continental rocks subducted to the depth of stishovite stability field (>300 km); (3) the tectonic setting and geodynamical mechanism of producing the HP-UHP metamorphic zones in the South Altyn Tagh, the North Qaidam and the North Qinling. Further studies aiming at these problems will make important progress not only in metamorphism of the HP-UHP rocks in the West and Middle Central China orogen, but also in continental deep subduction and exhumation in solid earth science. It will also contribute to the establishment of the theory of continental deep subduction.

A combined study of Cathodoluminescence (CL) imaging, LA-ICP-MS in situ trace element analysis and U-Pb dating was carried out on zircon grains from garnet-bearing muscovite-amphibole-albite gneiss and kyanite-bearing garnet-muscovite schist, the country rocks of the ultrahigh-pressure (UHP) eclogites in Yukahe area in the northern margin of Qaidam basin. Zircons from garnet-bearing muscovite-amphibole-albite gneiss mainly exhibit rounded crystal habits with internal sector and fir-tree zoning. The Th/U ratio and the content of REE and HREE of zircons are low. They are generally less than 0.01, 50 and 40 μg/g, respectively. All analyzed points display the REE pattern of a flat to right-sloping HREE profile with a slight positive Eu anomaly. These patterns indicate the presence of garnet and the absence of plagioclase in the peak metamorphic mineral assemblage. Zircons from kyanite-bearing garnet-muscovite schist display core-rim internal texture. The cores are larger in size than the rims and exhibit irregular shape and distinct or vague oscillatory zoning. The HREE content and the Th/U ratio of the core show large variations, varying from 22 to 1728 μg/g and from 0.01 to 0.82, respectively. These indicate that the cores represent relicts of the protolith that contained the detrital zircon. The rims are generally too narrow to date, except for three grains which exhibit metamorphic characteristics indicated by the low Th/U ratio, decreasing HREE enrichment and Eu anomaly. LA-ICP-MS U-Pb dating yielded peak metamorphic ages of 431±3 Ma and 432±19 Ma for the albite gneiss and the pelitic schist, respectively. These ages are consistent, within errors, with each other and also with the metamorphic age of the adjacent UHP eclogites (436±3 Ma and 431±4 Ma), as well as the coesite-bearing pelitic schist (423–432 Ma) in Yematan area. The almost identical metamorphic age of UHP eclogites and their country rocks, together with their field relationship, permit us to conclude that the Yukahe UHP metamorphic block was formed by continental deep subduction-collision during 430–435 Ma in early Paleozoic.

On the basis of Cathodoluminescence (CL) images and LA-ICP-MS in situ trace element analyses of zircons for finding the metamorphic age of eclogite and its country rock (garnet-biotite gneiss) from the Jianggalesayi area, Altyn Tagh, China, it is found that the zircon grains in eclogite mostly show homogeneous internal texture, and that few grains have residual cores, showing the typical magmatic origin characterized by the enrichment in HREE and high Th/U ratios generally higher than 0.4. On the other hand, the zircon rims and the homogeneous grains show that the REE pattern is flat or slightly depleted in HREE, which is the typical of metamorphic zircons coexisting with garnet. In addition, the zircon grains in garnet-biotite gneiss display a core-mantle-rim zoning texture, where the cores show the features of detrital zircons, and the mantles show the metamorphic features of zircons coexisting with garnet. By the LA-ICP-MS in situ dating of zircons, the metamorphic ages of eclogite, garnet-biotite gneiss, and the protolith of eclogite are calculated as 493 ± 4.3 Ma, 499 ± 27 Ma, and 754 ± 9 Ma, respectively. The metamorphic age of eclogite is almost the same as that of its country rock paragneiss and is about 250Ma later than its protolith age, which indicates that the ultrahigh-pressure (UHP) eclogite is the product of continental crust deep subduction.

Several microRNAs (miRs) have been found to have modulating effects on trophoblast functions, yet the biological role and function of miR-96-5p and its interaction with Dimethylarginine Dimethylaminohydrolase 1 (DDAH1) remained poorly understood.

The existing power supply reliability index system is oriented to power system without considering actual electricity availability in customer side. In addition, it is unable to reflect outage or customer's equipment shutdown caused by instantaneous interruption and power quality problem. This paper thus makes a systematic study on reliability of power customer. By comparing with power supply reliability, reliability of power customer is defined and extracted its evaluation requirements. An indexes system, consisting of seven customer indexes and two contrast indexes, are designed to describe reliability of power customer from continuity and availability. In order to comprehensively and quantitatively evaluate reliability of power customer in distribution networks, reliability evaluation method is proposed based on improved entropy method and the punishment weighting principle. Practical application has proved that reliability index system and evaluation method for power customer is reasonable and effective.