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SUMMARY The mechanism of present-day crustal deformation in southeast Tibet remains controversial. 3-D high-precision geodetic data can provide significant clues to analyse the key driving forces. Here, we conduct a series of 3-D finite-element modelling to investigate the influences of gravitational collapse, tectonic extrusion and mid-to-lower crustal flow on crustal deformation in southeast Tibet. The numerical results show that the gravitational collapse leads to predominant N-S extension and surface subsidence in the northern region, and predominant NW-SE compression and uplift in the southern region, which can explain the normal-faulting earthquakes in the interior. The gravity-driven horizontal velocity depends on the upper crustal viscosity, while the vertical velocity is determined by mid-to-lower crustal viscosity. The eastward tectonic extrusion causes slight southeastward rotation and predominant E-W compression in the northern region but has a little effect on the deformation in the southern region. By considering the joint effects of gravitational collapse and tectonic extrusion, we simulate the crustal deformation that reconciles with present-day geodetic observations. Both the two driving forces lead to positive shear strain rates along the major fault zones, with more contributions from the tectonic extrusion of the Tibetan Plateau. Constrained by the 3-D geodetic observations, the numerical results argue against the presence of massive fast mid-to-lower crustal flow from the Tibetan Plateau. Overall, the present-day crustal deformation in southeast Tibet is jointly driven by gravitational collapse and tectonic extrusion, which play distinct roles in shaping the faulting kinematics and regional strain partitioning.

Four derivative electrode materials have been obtained by selecting the calcination temperature based on the collapse point of a Ni-based coordination polymer precursor. Besides, their electrochemical performances are investigated.

Four different Cu/CuxO@C (x = 1 and 2) composites have been obtained and their electrochemical properties have also been investigated and compared.

The single-atomic-site doping of oxophilic-metal (Ru) species in FeCo-LDH leads to the active atom reconstruction at symmetry-breaking interfaces and then the excellent catalytic performance for OER/HER and overall water splitting at large current densities.

Owing to their optical, mechanical, and catalytic properties, plasmonic nanomaterials (P-NMs) have been widely used in sensing, disease treatment, as well as energy transfer and conversion applications. Therefore, the synthesis, properties, and applications of P-NMs have garnered significant interest in recent decades. This review surveys the various types of P-NMs, their synthesis methods, their properties, and recent applications. In addition, we summarize the current challenges and future developments in P-NMs. We hope this article will help researchers to gain a deeper understanding of P-NM applications in the field of energy, overcome the current problems associated with P-NMs, and develop novel P-NMs with better characteristics.

Based on the Global Navigation Satellite System (GNSS) velocity in North China from 1999 to 2018, the deformation parameters, such as the strain rate, the velocity profiles, and the fault slip rates, are analyzed. The principal conclusions are as follows: 1) the GNSS results during 1999–2007 can effectively reflect the deformation characteristics of North China, and the strain rate shows SEE tensile feature in the Shanxi seismic zone with a maximum value of 0.7 × 10−8/yr. Meanwhile, the deformation is characterized by left-lateral features in the Yinshan seismic zone and Zhangjiakou-Bohai seismic zone with a maximum shear strain rate of 0.7 × 10−8/yr. 2) In the period of 1999–2007, the GNSS velocity profiles show that the deformation is mainly distributed in a range of 100-km width crossing the Yinshan seismic zone and the middle section of the Zhangjiakou-Bohai seismic zone, and 50-km width crossing the Zhangjiakou-Bohai seismic zone near the Bohai Bay. 3) The deformation response to the 2011 Japan MW9.0 earthquake shows a significant difference between the middle and east sections of the Zhangjiakou-Bohai seismic zone, and the deformation loading rate decreased from 3.3 mm/yr in 1999–2007 to 2.6 mm/yr and 0.9 mm/yr in the 2013–2018 period for above two sections respectively. Furthermore, the fault slip rates inverted from GNSS measurements show a similar dynamic adjustment process, reflecting the weak impact of the Japan MW9.0 earthquake on the deformation around the central section of the Zhangjiakou-Bohai seismic zone. 4) From the results of GNSS strain rate, velocity profile and fault slip rate, we suggest that the potential of the strong earthquake should be high in the Yinshan seismic zone and the middle section of the Zhangjiakou-Bohai fault zone.

The correlation between seismicity and crustal deformation is investigated by introducing the earthquake catalogs from 1900 to 2019 and the Global Positioning System (GPS) strain rate during 1999–2007 in the Chinese mainland. The primary results show that (1) about 76.9% of earthquakes with M>6.5 since 1900 and 74.7% of events with M>5.5 between 1970 and 2019, occur in 30% of the region with high-strain rate; (2) the statistics of earthquakes greater than M 5.0 since 1990 show when temporally approaching to the time period of GPS observation, more earthquakes concentrated in the region with high-strain rate. In details, in a 9 yr statistics window, the ratio of cumulative seismicity that occurred in 30% of the high-strain rate regions from 2008 to 2017 is about 16.1%–20.7% lower than those in the previous two periods. Meanwhile, in a 4 yr statistics window, the ratios of cumulative seismicity that occurred in 30% of the high-strain rate regions in the periods of 2011–2015 and 2015–2019 are lower than other five periods by about 9.6%–31.2%. These periodic statistics show that high-strain rate matches well with the historical earthquakes (M≥5.0) than the future earthquake events. In general, the 9 yr GPS observations correspond well to the historical seismicity in the Chinese mainland, but the predicted effect for the future moderate earthquakes is not as good as that of the retrospective test.

A novel method, reduction followed by oxidation procedure, has been developed to fabricate efficient electrodes derived from metal-organic frameworks (MOFs), which were synthesized using terephthalic acid (TP) and 1,3,5-benzenetricarboxylic acid (BTC) as organic ligands. The copper-based composites, namely Cu/Cu

Silicon (Si) materials as anode materials for applications in lithium-ion batteries (LIBs) have received increasing attention. Among the Si materials, the electrochemical properties of SiOx-based (0

Transition metal hydroxides are a kind of promising electrode material in electrochemical energy storage, but the poor conductivity limits their application. Lanthanides are good proton conductors and can usually improve the intrinsic conductivity of other materials. By integrating the merits of lanthanide elements and transition metal hydroxide, we designed lanthanum oxide nickel hydroxide composites (LONH) with unique ultrathin triangle nanosheet morphology via a controllable synthetic strategy for high-performance supercapacitors. When the LONH is used as positive electrode material in aqueous asymmetric supercapacitor, it reveals an energy density (107.8 W h kg−1 at 800 W kg−1), rate performance (86.9% retention at 4 kW kg−1) and outstanding cycle stability (more than 90% retention after 3,000 cycles). This work confirms that compositing La2O3 and Ni(OH)2 can significantly improve the supercapacitor performance of both pristine La2O3 and transition metal hydroxide composites. We hope this work would offer a good prospect for developing other lanthanide-transition metal hydroxide composites as an attractive class of electrode materials in electrochemical energy storage.

By integrating the merits of lanthanide elements and quantum dots, we firstly design CeO2 quantum dots doped Ni-Co hydroxide nanosheet via a controllable synthetic strategy, which exhibits a large specific capacitance (1370.7 F/g at 1.0 A/g) and a good cyclic stability (90.6% retention after 4000 cycles). Moreover, we assemble an aqueous asymmetric supercapacitor with the obtained material, which has an extremely high energy density (108.9 Wh/kg at 378 W/kg) and outstanding cycle stability (retaining 88.1% capacitance at 2.0 A/g after 4000 cycles).

The elusive hydrogen-bonded sulfur monoxide–hydroxyl radical complex (•OH···OS), a missing intermediate in the atmospheric chemistry of SO2, was generated in the 266 nm laser photolysis of the sulf...

Introduction of surface defects and phase control engineering in the electrocatalytic system of overall water splitting has played a crucial role in significantly enhancing its electrocatalytic activity toward the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in water splitting, but the relationship between structure and electrocatalysis is still elusive. Herein, we report a solid–liquid method to induce surface reorganization (formation of a chalcogenide layer with rich chalcogenide vacancies) and phase transformation (Co9S8-to-Co3S4) simultaneously on cobalt chalcogenide. Featuring a uniform 2D morphology and the in situ formation of sulfur (S) vacancies, in a 0.1 M KOH solution, it exhibits a low overpotential of 288 mV vs. RHE at 10 mA cm−2, a low Tafel slope of 43.4 mV dec−1, and strong cycling stability (35 h), outperforming commercial RuO2 and most reported OER electrocatalysts. In addition, we also investigate the OER activity of the Co–S–P electrode in 1.0 M KOH solutions. Co0.37S0.38P0.02 NSs only need 257 mV to reach a current density of 10 mA cm−2. Meanwhile, the Tafel slope of Co0.37S0.38P0.02 NSs (44.0 mV dec−1) is lower than those of other recently reported electrocatalysts. Also, it shows high HER electrocatalytic activity in alkaline and acidic solutions. Finally, the Co0.37S0.38P0.02 electrode is used as a cathode and anode simultaneously for overall water splitting, which merely requires a cell voltage of 1.59 V at 10 mA cm−2 with excellent stability (40 h).

Small molecules solely consisting of H, N, O, and S are highly relevant intermediates in atmospheric chemistry and biology. Even though several isomers of [HNO2S] have been computationally predicted, only the IR spectra for the two lowest-energy isomers HNSO2 and syn–syn HONSO have been previously reported. Herein, the photochemistry (193 nm laser) of HNSO2 in N2-, Ne-, and Ar-matrices (≤15 K) has been studied. Aside from syn–syn HONSO, several new isomers including anti–syn HONSO, gauche–syn HOSNO, syn HOS(O)N, anti HOS(O)N, syn HS(O)NO, anti HN(O)SO, gauche–syn HSONO, and an elusive caged-radical pair HOS˙⋯˙NO have been identified. Additionally, the formation of fragments HONO, HO˙, ˙NO, and ˙NO2 has also been observed. The characterization of these species with matrix-isolation IR and UV/Vis spectroscopy is supported by 15N-labeling and quantum chemical computations at the B3LYP/6-311++G(3df,3pd) level. Furthermore, the photo-induced isomerization reactions, including the conformational conversion of syn–syn HONSO → anti–syn HONSO and reversible isomerization of HOSNO ↔ anti–syn HONSO, syn–syn HONSO ↔ HN(O)SO, HSONO ↔ HS(O)NO, and HOS˙⋯˙NO ↔ HOSNO have also been observed, and the underlying mechanism is discussed.

Transition metal cobaltites and their composite materials have high charge storage and electron transport capacities due to their multidimensional morphological structures. In recent years, transition metal cobaltites have become a research hotspot in the field of electrochemistry due to their natural abundance, safety and low cost. In this paper, recent advances in the electrochemical application of transition metal cobaltites and their composites as electrode materials or as electrocatalysts in electrochemistry, such as supercapacitors (SCs), lithium-ion batteries (LIBs), electrocatalysts and electrochemical sensors, are introduced. The effects of the nanostructures of transition metal cobaltites on their electrochemical properties and other development strategies are discussed. Finally, the problems that need to be overcome to further improve the electrochemical properties of cobaltites are summarized, and developmental directions for transition metal cobaltites and their composites in the field of electrochemistry are proposed.

Methoxyphosphinidene oxide (CH3 OPO) and isomeric methyldioxophosphorane (CH3 PO2 ) are key intermediates in the degradation of organophosphorus compounds (OPCs). Unlike the nitrogen analogues CH3 ONO and CH3 NO2 , the experimental data for these two prototypical OPCs are scarce. By high-vacuum flash pyrolysis (HVFP) of the diazide CH3 OP(O)(N3 )2 at 1000 K, the cis and trans conformers of CH3 OPO have been generated in the gas phase and subsequently isolated in cryogenic Ar and N2 matrices for IR spectroscopic characterization. Upon 266 nm laser irradiation of CH3 OPO, cis→trans conformational conversion occurs with concurrent isomerization to CH3 PO2 . The spectroscopic identification of CH3 OPO and CH3 PO2 is supported by D-, 13 C-, and 18 O-isotope labeling and quantum chemical calculations at the CCSD(T)-F12a/cc-pVTZ-F12 level using configuration-selective vibrational configuration interaction (VCI).

In recent years, Co-based metal-organic framework have drawn increasing attention as electrochemical applications due to their facile preparation methods, adjustable sizes, tunable structures and high specific surface areas. However, deficiency like poor electrical conductivity of pristine Co-based metal-organic framework have limited their further application. Hence, their composites and derivatives possessing specific property have arouse many researchers’ attention and been widely used in the fields of energy conversion and storage. Here, relevant synthetic processes, morphologies and electrochemical performances of cobalt-based metal-organic framework composites and their derivatives for applications in electrocatalysis, rechargeable batteries and supercapacitors are reviewed and summarized.

The hydrogen evolution reaction (HER) is an ideal model to explore the effect between the activity and the surface vacancy of catalysts. Compared to the anion vacancy, the cation vacancy is more challenging to selectively generate due to the large formation energy, and the serious lack of insight into the structure-activity relationship of cation vacancy-rich catalysts. Herein, we report a facile solid-liquid phase chemical strategy for in situ formation of cation vacancies in a five-fold twinned PtPdRuTe anisotropic structure (v-Pd3Pt29Ru62Te6 AS). Five-fold twinned AS with metal vacancies preferentially produced is confirmed by both X-ray photoelectron spectroscopy (XPS) and high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM). Due to the synergy of metal vacancies and twinned structural advantages, including the appropriate hydrogen binding energy, large exposed surface, anisotropic structure and fast mass/charge transport, v-Pd3Pt29Ru62Te6 AS exhibits significantly enhanced HER electrocatalytic performance in both alkaline and acidic solutions, with ultrasmall overpotentials of 22 and 39 mV to achieve 10 mA cm−2, respectively, and remarkable long-term stability (at least 30 h). These results herald a promising strategy to utilize defective twinned materials for advanced energy storage applications.

Among various manganese-based oxides or hydroxides, manganite (γ-MnOOH) has been regarded as an important participant for high-performance electrochemical energy storage and electrocatalysis. Effor...

Seabed liquefaction occurs frequently under waves in coastal areas due to accumulation of excess pore water pressure. During wave-induced liquefaction, submarine silty soil fluctuates like a fluid. In this study, a set of falling-ball test devices was made and used to measure the viscosity coefficient of liquefied silty soil during silty soil fluctuation experiments. Smooth density balls (copper, iron, and zirconia) of three different densities were used. A laser displacement sensor was used to record the displacement of the density ball with time. Each density ball sank at a constant speed when the forces on the ball reached equilibrium. According to the result of the force analysis, the movement of a density ball in this period could be regarded as vertical uniform motion, and the ratio of displacement to time was used as the sinking speed. Therefore, the viscosity coefficient of liquefied soil was calculated via Stokes’ law. Because of the smaller density and the effect of the movement of liquefied soil, there was a large error with the measurement of the zirconia ball in the falling-ball method. Therefore, the data for other density balls (excluding zirconia balls) were selected. The results showed that the range of the viscosity coefficient of the liquefied silty soil was 0.81–1.71 kPa s. The fluctuation amplitude of the liquefied soil and the effects of soil action on viscosity measurements were also evaluated. Thus, Stokes’ law can be used to calculate the viscosity coefficient of liquefied silty soil by the falling-ball method.

A simple one-pot approach to the in situ construction of ultrathin shells is developed to create a new highly efficient and durable Pt-based electrocatalyst for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). Herein, the synthesized ultrathin PdPtAg-shells are located on twinned PdAg nanocrystals and deposited onto graphene (G) (denoted by PdAg@PdPtAg/rGO). The PdAg@PdPtAg/rGO nanocrystal shows a low overpotential of 22 mV at 10 mA cm−2 and excellent electrochemical stability with 99.5% retention over either 12 h or 30 000 cycles of HER. Meanwhile, its ORR activities in acidic and alkaline media are very high and better than that of commercially available Pt/C. Both the experimental and calculated results suggest that the presence of an ultrathin PdPtAg alloy shell synthesized on a PdAg twinned support is the main reason for the greatly enhanced activities. Moreover, the twinned PdAg nanocrystal provides a number of twinned grain boundaries and defect sites (such as step, edge and kink sites). This typical structure represents a new strategy for synthesizing high-performance Pt-based catalysts, promoting their practical applications in energy conversion and storage devices.

S-Nitrosothiols (RSNO) are exogenous and endogenous sources of nitric oxide in biological systems due to facile homolytic cleavage of the S-N bonds. By following the photolytic decomposition of prototypical RSNO (R = Me and Et) in Ne, Ar, and N2 matrixes (

The integration of different active sites into metallic catalysts, which may impart new properties and functionalities, is desirable yet challenging. Herein, a novel strategy is demonstrated to integrate atomic vacancies onto a twinned Pd2CoAg surface. This strategy shows that such integration is highly efficient for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) catalysis at room temperature. We characterize the composition and structure of the twinned Pd2CoAg nanocrystals with vacancy (v-Pd2CoAg NCs) interfaces and it is shown that the Co addition not only increases the atomic vacancies of Pd2Ag twinned interface, but also leads to the formation of oxygen vacancies on the surface of CoOx. The synergistic effect of the surface atomic vacancies and metal twinned interfaces of v-Pd2CoAg NCs can tune the charge-density distribution on the surface of the electrocatalysts, and result in a 5 times increase in ORR mass activity than that of Pt/C at 0.9 V. This study provides a foundation for the rational design of ‘active sites’ for practical HER and ORR electrocatalysts.

Defect engineering is widely applied in transition metal dichalcogenides to produce high-purity hydrogen. However, the instability of vacancy states on catalysis still remains a considerable challenge. Here, our first-principles calculations showed that, by optimizing the asymmetric S vacancy in the highly asymmetric 1T' crystal of layered bitransition metal dichalcogenides (Co-MoS2) in light of Pd modulation, the relative amount of metastable phase and the quantity of active sites in the structure can be reduced and increased, respectively, leading to a further boosted hydrogen evolution reaction (HER) activity toward layered bi-transition metal dichalcogenides. Thus, we then used a "click" chemistry strategy to make such a catalyst with engineered unsaturated sulfur edges via a strong coupling effect between ultrafine Pd ensembles and Co-MoS2 nanosheets. As expected, the Pd-modulated Co-MoS2 nanosheets exhibited a very low overpotential of 60 mV at 10 mA cm-2 with a small Tafel slope (56 mV dec-1) for the HER in 1.0 M PBS, comparable to those of commercial Pt/C. In addition, their high HER activity was retained in acidic and alkaline conditions. Both the theoretical and experimental results revealed that Pd ensembles can efficiently activate and stabilize the inert basal plane S sites during HER processes as a result of the formation of Pd-S in Co-MoS2. This work not only provides a deeper understanding of the correlation between defect sites and intrinsic HER catalytic properties for transition metal chalcogenide (TMD)-based catalysts, but also offers new insights into better designing earth-abundant HER catalysts displaying high efficiency and durability.

The submarine pipelines that are buried in the Yellow River subaqueous delta can be subject to fluctuant local-liquefied soil caused by storm wave action, possibly causing pipeline damage. An experimental investigation was carried out in a wave flume to study the horizontal normal force on buried rigid pipelines in fluctuant liquefied soil. In this experiment, the soil bed was made of silt from the Yellow River Delta, whereas a steel pipe served as pipeline. Under the experimental conditions, the normal force range on the pipeline in fluctuant liquefied soil was several times higher than that in stable soil, specifically on the side of the pipeline exposed to the wave direction. The resultant force of the horizontal normal forces on the buried pipeline grew by about one order of magnitude after soil liquefaction.