The control of multimetallic ensembles at the atomic‐level is challenging, especially for high‐entropy alloys (HEAs) possessing five or more elements. Herein, the one‐pot synthesis of hexagonal‐close‐packed (hcp) PtRhBiSnSb high‐entropy intermetallic (HEI) nanoplates with intrinsically isolated Pt, Rh, Bi, Sn, and Sb atoms is reported, to boost the electrochemical oxidation of liquid fuels. Taking advantage of these combined five metals, the well‐defined PtRhBiSnSb HEI nanoplates exhibit a remarkable mass activity of 19.529, 15.558, and 7.535 A mg−1Pt+Rh toward the electrooxidation of methanol, ethanol, and glycerol in alkaline electrolytes, respectively, representing a state‐of‐the‐art multifunctional electrocatalyst for alcohol oxidation reactions. In particular, the PtRhBiSnSb HEI achieves record‐high methanol oxidation reaction (MOR) activity in an alkaline environment. Theoretical calculations demonstrate that the introduction of the fifth metal Rh enhances the electron‐transfer efficiency in PtRhBiSnSb HEI nanoplates, which contributes to the improved oxidation capability. Meanwhile, robust electronic structures of the active sites are achieved due to the synergistic protections from Bi, Sn, and Sb sites. This work offers significant research advances in developing well‐defined HEA with delicate control over compositions and properties.

[1] We investigated properties of frictional sliding of plagioclase, pyroxene, and their mixture gouges with a small amount of hornblende, biotite, and quartz as accessory minerals, under hydrothermal conditions with an effective normal stress of 200 MPa, pore pressure of 30 MPa, and temperatures from 100°C to 600°C. Axial loading rate was stepped between 0.001 and 0.0001 mm/s to acquire the rate dependence. Both plagioclase and pyroxene gouges showed velocity-weakening behavior in the whole temperature range except the velocity-strengthening behavior of pyroxene at 200°C. For temperatures above 400°C, both plagioclase and pyroxene gouges showed oscillatory slips, as a result of small d c values of 3-4 μm which make the critical stiffness rise remarkably and approach the system stiffness. Above 300°C, the direct effect of plagioclase shows an increasing trend with temperature, indicating control of the deformation process by thermally activated mechanisms. As the difference of a and b values here are only 20% at most, this trend also applies to the evolution effect. Our analytical derivation based on the theory of pressure solution shows a log-linear contact area growth with time that corresponds to an evolution effect, and estimations based on this encompass the plagioclase data, though the identification of actual mechanisms is not easy. Finally, it is found that a little quartz (3-5%) added to the plagioclase (60-62%)-pyroxene (35%) mixture has a strong stabilizing effect, leading to a transition from velocity weakening to velocity strengthening. These results may help constrain the depth range of seismic slips on deep faults in the lower crust of gabbroic composition.Citation: He, C., L. Luo, Q.-M. Hao, and Y. Zhou (2013), Velocity-weakening behavior of plagioclase and pyroxene gouges and stabilizing effect of small amounts of quartz under hydrothermal conditions,

This work reports the nanocomposites of graphitic nanofibers (GNFs) and carbon nanotubes (CNTs) as the electrode material for supercapacitors. The hybrid CNTs/GNFs was prepared via a synthesis route that involved catalytic chemical vapor deposition (CVD) method. The structure and morphology of CNTs/GNFs can be precisely controlled by adjusting the flow rates of reactant gases. The nest shape entanglement of CNTs and GNFs which could not only have high conductivity to facilitate ion transmission, but could also increase surface area for more electrolyte ions access. When assembled in a symmetric two-electrode system, the CNTs/GNFs-based supercapacitor showed a very good cycling stability of 96% after 10 000 charge/discharge cycles. Moreover, CNTs/GNFs-based symmetric device can deliver a maximum specific energy of 72.2 Wh kg−1 at a power density of 686.0 W kg−1. The high performance of the hybrid performance can be attributed to the wheat like GNFs which provide sufficient accessible sites for charge storage, and the CNTs skeleton which provide channels for charge transport.

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We relocated 13367 small earthquakes that occurred in western Sichuan between 1992 and 2002 using a double‐difference (DD) earthquake location algorithm to improve the relative location precision. The relocated microseismicity forms highly organized structures that correlate with the surface faulting well: showing the flower structure across the simple strike‐slip fault, and the organized but dispersed structure across the pull‐apart basin and thrust fault. Beneath thrust fault, there exists an aseismic layer. The seismicity shows segmentation characteristics on active fault zones. Other significant tectonic features that were previously obscured by routine location errors are also revealed by the relocated seismicity. Some blind faults are delineated by lineages of seismicity that are suggestive of faulting structures. A series of large voids in seismicity appear with dimensions of tens of kilometers on the Xianshuihe‐Anninghe‐Zemuhe fault zone that have been aseismic over the 10‐year time interval, suggesting that these segments may be locked and storing strain energy for release in future large earthquakes. A 5km thick aseismic layer appears in most places in western Sichuan plateau at depths of 15~20km. The crustal strength envelopes are calculated for the western Sichuan plateau based on the results from hightemperature and high‐pressure experiments. The result shows that the granite at depths of 14 to 19km appears to be ductile, which is in good agreement with the thickness and depth range of the aseismic layer, suggesting that the aseismic layer may be the result of the ductile deformation from the granite in the upper crust.

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