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Our understanding of plate boundary deformation has been enhanced by transient signals observed against the backdrop of time-independent secular motions. We make use of a new analysis of displacement time series from about 1,000 continuous Global Positioning System (GPS) stations in California from 1999 to 2018 to distinguish tectonic and nontectonic transients from secular motion. A primary objective is to define a high-resolution three-dimensional reference frame (datum) for California that can be rapidly maintained with geodetic data to accommodate both secular and time-dependent motions. To this end, we compare the displacements to those predicted by a horizontal secular fault slip model for the region and construct displacement and strain rate fields. Over the past 19 years, California has experienced 19 geodetically detectable earthquakes and widespread postseismic deformation. We observe postseismic strain rate variations as large as 1,000 nstrain/year with moment releases equivalent up to an Mw6.8 earthquake. We find significant secular differences up to 10 mm/year with the fault slip model, from the Mendocino Triple Junction to the southern Cascadia subduction zone, the northern Basin and Range, and the Santa Barbara channel. Secular vertical uplift is observed across the Transverse Ranges, Coastal Ranges, Sierra Nevada, as well as large-scale postseismic uplift after the 1999 Mw7.1 Hector Mine and 2010 Mw7.2 El Mayor-Cucapah earthquakes. We also identify areas of vertical land motions due to anthropogenic, natural, and magmatic processes. Finally, we demonstrate the utility of the kinematic datum by improving the accuracy of high-spatial-resolution 12-day repeat-cycle Sentinel-1 Interferometric Synthetic Aperture Radar displacement and velocity maps.

In the past decades, the rapid depletion of non‐renewable energy sources has caused growing energy crisis and increasing emissions of carbon dioxide (CO2), which aggravates global warming and catastrophic climate change. Electrocatalysis is regarded as an effective method for consuming atmospheric CO2 and simultaneously alleviating the energy problem by converting CO2 into high value‐added chemicals. Amorphous nanomaterials with long‐range disordered structures possess abundant highly unsaturated atomic sites and dangling bonds on their surfaces, thus providing a large number of active sites, and show unique electronic structures compared to their crystalline counterparts due to the distinct atomic arrangements. Therefore, amorphous nanomaterials are recently demonstrated as highly efficient catalysts for diverse electrocatalytic reactions, including electrocatalytic CO2 reduction reaction (CO2RR). Here the rational synthesis and electrocatalytic performance of newly emerging amorphous nanomaterials will be outlined for electrocatalytic CO2RR. Importantly, the intrinsic merits of these amorphous catalysts in CO2RR processes will be summarized and highlighted. Finally, these perspectives on the remaining challenges and some potential future directions in this emerging field will also be provided. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (CO2RR) converts the greenhouse gas CO2 into valuable chemicals under mild conditions and is considered a promising approach to reaching carbon neutralization. However, its efficiency and selectivity towards desired products remain far below the requirements for industrial implementation because of its complex reaction mechanism and diverse intermediates. Particularly, the C–C coupling step in the CO2RR is the key step to ensure a high yield of value-added multi-carbon products. Herein, we discuss a recently developed approach to facilitate the C–C coupling step via the rational tuning of the local microenvironment around active sites. First, recent progress and the mechanism of the CO2RR are briefly described. Next, representative approaches of catalyst engineering, including tandem catalysis, molecular modification, micro-structure regulation, proton donation, hydrophobicity and electric field effect, are highlighted to enrich or regulate the intermediates. Finally, persistent technological challenges are summarized and several personal perspectives are provided to propel the industrial application of the CO2RR. [ABSTRACT FROM AUTHOR]

On 22 May 2021, an earthquake (98.3° E and 34.59° N) struck Maduo town in Qinghai province, occurring along a relatively obscure secondary fault within the block. We utilized 105 archived Sentinel-1A/B acquisitions to investigate the coseismic deformation and the evolution of postseismic displacements in both the temporal and spatial domains, as well as the associated dynamic mechanisms of the 2021 Maduo earthquake. The interference fringes and coseismic deformation revealed that the primary feature of this event was the rupture along a left-lateral strike-slip fault. The released seismic moment was close to 1.88 ×   10 20   N · m , which is equivalent to an Mw 7.45 event. Simultaneously, the maximum coseismic slip reached approximately 4 m along the fault plane. The evolution of postseismic displacements in both the temporal and spatial domains over 450 days following the mainshock was further analyzed to explore the underlying physical mechanisms. Generally, the patterns of coseismic slip and afterslip were similar, although the postseismic displacements decayed rapidly over time. The modeled afterslip downdip of the coseismic rupture (at depths of 15–40 km) effectively explains the postseismic deformation, with a released moment estimated at 4.57 ×   10 19   N · m (corresponding to Mw 7.04). Additionally, we found that regions with high coseismic slip tend to exhibit weak seismicity, and that afterslip and aftershocks are likely driven by each other. Finally, we estimated the Coulomb Failure Stress changes ( Δ C F S ) triggered by both coseismic rupture and aseismic slip resulting from this event. The co- and postseismic Δ C F S show similar patterns, but the magnitude of the postseismic Δ C F S is much lower ( ≤ 0.01 MPa). We found that Δ C F S notably increased on the Yushu segment of the Garze-Yushu-Xianshuihe Fault (GYXF), as well as the Maqin–Maqu and Tuosuo Lake sections of the East Kunlun Fault (EKF). Therefore, we infer that these fault segments may have a higher potential seismic risk and should be carefully monitored in the future. [ABSTRACT FROM AUTHOR]

Developing an intermediate-temperature solid oxide fuel cell (IT-SOFC) is one of the most promising ways of achieving carbon neutrality, but its air-electrode is restricted by the conflict between the sluggish catalytic activity and durability. Herein, an A-site high-entropy perovskite composite La0.2Ba0.2Sr0.2Ca0.2Ce0.2−xCoO3−δ–xCeO2 (LBSCCC–CeO2) air-electrode material is fabricated via a one-step self-constructing strategy, which shows excellent oxygen reduction activity and stability due to the high-entropy structure and the synergy effect between LBSCCC and interfacial CeO2. This work provides a new way of fabricating high-performance air-electrodes in IT-SOFCs. [ABSTRACT FROM AUTHOR]