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Novel dual-ionic imidazolium salts are shown to display excellent catalytic activity for cycloaddition of carbon dioxide and epoxides under room temperature and atmospheric pressure (0.1 MPa) without any solvent and co-catalyst leading to 96.1% product yield. It can be reused five times to keep the product yield over 90%. These intriguing results are attributed to a new reaction mechanism, which is supported by theoretical calculations along with the measurements of 13C NMR spectrum and Fourier transform infrared spectroscopy (FT-IR). The excellent catalytic activity can be traced to a CO2-philic group along with an electrophilic hydrogen atom. Our work shows that incorporation of CO2-philic group is an feasible pathway to develop the new efficient ionic liquids.

The application of Si as the anode materials for lithium-ion batteries (LIBs) is still severely hindered by the rapid capacity decay due to the structural damage caused by large volume change (>300%) during cycling. Herein, a three-dimensional (3D) aerogel anode of Si@carbon@graphene (SCG) is rationally constructed via a polydopamine-assisted strategy. Polydopamine is coated on Si nanoparticles to serve as an interface linker to initiate the assembly of Si and graphene oxide, which plays a crucial role in the successful fabrication of SCG aerogels. After annealing the polydopamine is converted into N-doped carbon (N-carbon) coatings to protect Si materials. The dual protection from N-carbon and graphene aerogels synergistically improves the structural stability and electronic conductivity of Si, thereby leading to the significantly improved lithium storage properties. Electrochemical tests show that the SCG with optimized graphene content delivers a high capacity (712 mAh/g at 100 mA/g) and robust cycling stability (402 mAh/g at 1 A/g after 1500 cycles). Furthermore, the full cell using SCG aerogels as anode exhibits a reversible capacity of 187.6 mAh/g after 80 cycles at 0.1 A/g. This work provides a plausible strategy for developing Si anode in LIBs.

Lithium-sulfur (Li-S) batteries are considered as one of the promising next-generation energy storage systems because of their high energy density. While the low utilization of sulfur and sluggish reaction kinetics would lead to degradation of electrochemical performance and thus hinder the practical application of Li-S batteries. Herein, a double-shelled TiO2-graphene heterostructure (H-TiO2/rGO) with abundant oxygen vacancies (OVs) and highly exposed active plane as advanced host material in Li-S batteries is designed. This rational structure not only provides sufficient active sites and lower bandgap for lithium polysulfides (LiPSs), but also builds smooth adsorption-diffusion-conversion of LiPSs on catalyst, which greatly reduces interfacial energy barrier and promotes the utilization of sulfur through suppressing the devastating shuttling effect. Combining the synergetic merits of strong anchoring ability and catalyzing the of LiPSs, the electrode (S-TiO2/rGO-1) exhibits superior rate performance and long lifespan (1000 cycles at 1C, 0.023% capacity loss per cycle) with high columbic efficiency. This work paves an alternative way to establish smooth adsorption-diffusion-conversion of polysulfides on catalyst in Li-S batteries and provides a new sight to understand catalyst design in energy storage devices.

The rational design of oxygen vacancies and electronic microstructures of electrode materials for energy storage devices still remains a challenge. Herein, we synthesize nickel cobalt-based oxides nanoflower arrays assembled with nanowires grown on Ni foam via the hydrothermal process followed annealing process in air and argon atmospheres respectively. It is found that the annealing atmosphere has a vital influence on the oxygen vacancies and electronic microstructures of resulting NiCo2O4 (NCO-Air) and CoNiO2 (NCO-Ar) products, which NCO-Ar has more oxygen vacancies and larger specific surface area of 163.48 m2/g. The density functional theory calculation reveals that more oxygen vacancies can provide more electrons to adsorb -OH free anions resulting in superior electrochemical energy storage performance. Therefore, the assembled asymmetric supercapacitor of NCO-Ar//active carbon delivers an excellent energy density of 112.52 Wh/kg at a power density of 558.73 W/kg and the fabricated NCO-Ar//Zn battery presents the specific capacity of 180.20 mAh/g and energy density of 308.14 Wh/kg. The experimental measurement and theoretical calculation not only provide a facile strategy to construct flower-like mesoporous architectures with massive oxygen vacancies, but also demonstrate that NCO-Ar is an ideal electrode material for the next generation of energy storage devices.

Rock engineering is highly susceptible to cyclic loads resulting from earthquakes, quarrying or rockbursts. Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment of rock engineering structures. So far, significant progress has been gained on the mechanical characteristics of rocks subjected to cyclic loading. For providing a global insight of typical results and main features of rocks under cyclic loading conditions, this study comprehensively reviews the state-of-the-art of deformation and failure mechanism and fatigue constitutive relationship of rocks subjected to cyclic loading in the past 60 years. Firstly, cyclic tests on rocks are classified into different types based on loading paths, loading parameters, loading types and environment conditions. Secondly, representative results are summarized and highlighted in terms of the fatigue response of rocks, including the deformation degradation, energy dissipation, damage evolution and failure characteristics; both laboratory testing and numerical results are presented, and various measurement techniques such as X-ray micro-computed tomography (micro-CT) and digital image correlation (DIC) are considered. Thirdly, the influences of cyclic loads on the mechanical characteristics of rocks are discussed, including the cyclic stress, frequency, amplitude and waveform. Subsequently, constitutive relationships for rocks subjected to cyclic loading are outlined, in which typical fatigue constitutive models are compared and analyzed, regarding the elastoplastic model, the internal variable model, the energy-based damage model and the discrete element-based model. Finally, some ambiguous questions and prospective research are interpreted and discussed.

Semi-competing risks data, including probably correlated non-terminal event and terminal event times, are frequently encountered in medical research. Work on semi-competing risks data has mainly focused on the situations without or only with low-dimensional covariates. However, high and ultra-high dimensional data have been very common in modern scientific research. In this article, we propose a model-free feature screening procedure for ultra-high dimensional semi-competing risks data to discover features contributing separately or jointly to non-terminal and terminal event times via Kolmogorov–Smirnov statistics. This new approach could be used for contexts with discrete, categorical and continuous covariates, which is achieved through the technique of slice-and-fuse. It enjoys several desirable advantages inherited in the Kolmogorov–Smirnov statistics. Under rather mild conditions, we show that the newly suggested method possesses sure screening property. Monte-Carlo simulation studies are conducted to investigate the finite sample properties of our proposed procedure and make comparisons with existing methods, while a real data example is also offered for illustration.

Recycling of valuable metals from spent catalysts in a green way is gaining extensive interest for economic and environment reasons. In this study, we developed novel hydrophobic deep eutectic solvents to extract Mo from spent catalysts. The hydrophobic DESs have been designed and synthesized by mixing one molar of the quaternary ammonium salt and two molars of various saturated fatty acids with different carbon chain lengths. The extraction ability and extraction mechanism of these DESs were studied, some factors influencing the extraction efficiency, including the structure of hydrogen bond acceptors and hydrogen bond donors, initial aqueous pH, reaction time and temperature, phase ratios were investigated. It is found that the synthesized hydrophobic DESs exhibit excellent extraction performance toward Mo, where the Mo distribution ratio is more than 2200 in the presence of other metals, corresponding to an extraction efficiency of 99% at optimal reaction conditions. This work reveals a distinct class of materials, guiding an effective and green way for spent catalyst treatment.Implications: Novel hydrophobic deep eutectic solvents have been developed to extract Mo from spent catalysts, the synthesized hydrophobic DESs possess several advantages, such as green, low price, low toxicity, and biodegradability. It exhibits excellent extraction performance under an optimized extraction condition. This work reveals a distinct class of materials, guiding a promising way for green and economical utilization of spent catalysts.

Genes containing GTP_EFTU domain mainly express elongation factors (EF), Small GTPases, and GTP-binding proteins, which are closely related to protein synthesis, extension and ATP synthesis. In this study, we identified 39 genes containing GTP_EFTU domains from peppers. The evolutionary trees constructed from capsicum, Arabidopsis, rice, and tomato are mainly divided into 7 subfamilies. Using PacBio (Pacific Biosciences) sequencing and assembly data, we extracted these 39 gene sequences, from which 25 genes had alternative splicing. Particularly, the Capana08g000545 had 16 alternative splicing processes. Accordingly, we performed promoter sequence analysis, subcellular location prediction, the expression analysis of different tissues and periods, and also the GO (Gene ontology) analysis of co-expressed genes. Lastly we did the qRT-PCR analysis in 5 stages of pepper fruit development. These analyses revealed important structural and functional information for the identified 39 genes that contain GTP_EFTU domains, providing important references for further follow-up experiments to verify the genes function on plants or their unique roles in peppers.

For the first time, a group of CaB6-typed cubic rare earth high-entropy hexaborides have been successfully fabricated into dense bulk pellets (>98.5 % in relative densities). The specimens are prepared from elemental precursors via in-situ metal-boron reactive spark plasma sintering. The sintered bulk pellets are determined to be single-phase without any detectable oxides or other secondary phases. The homogenous elemental distributions have been confirmed at both microscale and nanoscale. The Vickers microhardness are measured to be 16−18 GPa at a standard indentation load of 9.8 N. The nanoindentation hardness and Young’s moduli have been measured to be 19−22 GPa and 190−250 GPa, respectively, by nanoindentation test using a maximum load of 500 mN. The material work functions are determined to be 3.7–4.0 eV by ultraviolet photoelectron spectroscopy characterizations, which are significantly higher than that of LaB6.

The mesopelagic zone (200–1000 m depth) contains high fish species diversity but biomass and abundances are uncertain yet essential to understand ecosystem functioning. Hull-mounted acoustic systems (usually 38 kHz) often make assumptions on average target strength (TS) of mesopelagic fish assemblages when estimating biomass/abundance. Here, an unsupervised clustering algorithm was applied on broadband acoustic data (54–78 kHz), collected by a towed instrumented platform in the central Northeast Atlantic, to identify different mesopelagic target types based on similarity of individual TS spectra. Numerical density estimates from echo-counting showed spatial differences in vertical distribution patterns of the different target types and TS spectra data suggested that >30% of the gas-bearing targets had high resonance frequencies (>60 kHz) with low scattering strength at 38 kHz. This conceptual study highlights the importance of separating targets into different target groups to obtain correct backscatter information and to account for all relevant scatterers when estimating average TS at 38 kHz, in order to achieve more accurate biomass/abundance estimates. It furthermore demonstrates the use of a towed broadband acoustic platform for fine-scale numerical density estimates as a complementary method to hull-mounted acoustic data to increase knowledge on mesopelagic ecosystem structure.

The work presents the application of support vector machine (SVM) with Graphics Processing Unit (GPU) acceleration in developing a regional forecast model for the ionospheric total electron content (TEC) over China region. In this study, the SVM model has the past TEC values as inputs as well as 26 input parameters, which include the ionospheric diurnal variation, seasonal variation, spatial variation, solar activity, geomagnetic activity, and thermospheric wind. The output is the TEC values up to 1 h ahead. Datasets for 2016–2017 are used to train the SVM, and datasets for 2018 are selected as the test dataset to verify the SVM model performance. Predictions from the SVM model, back propagation-based NN (BP-NN) model, and International Reference Ionosphere 2016 (IRI2016) model are then compared with the Global TEC grid data released by IGS in China. According to the predicting results, the root-mean-square-error (RMSE) of SVM model ranges from 1.31 to 1.64 TECU, the relative error (RE) is 10.73–15.86%, and the correlation coefficient falls within the range of 0.92–0.99. The BP-NN model’s RMSE varies between 1.61 and 2.26 TECU, RE is between 13.77 and 20.19%, and the correlation coefficient lies in the range of 0.90–0.98. For the IRI2016 model, the RMSE, RE and correlation coefficient ranges are 2.21–5.73 TECU, 27.36–40.31%, and 0.83–0.95, respectively. Combined with the comparison of diurnal variations of TEC, it suggests that the SVM model greatly outperforms the BP-NN and IRI2016 models. Furthermore, the variation of seasonal and local characteristics is also validated by the SVM model. The results indicate that the SVM model accelerated by GPU is very promising for applications in ionospheric studies.

In theory, the industrial agglomeration is a double-edged sword as there are both positive and negative externalities. China’s cities, with great disparities on degrees of the industrial agglomeration, often face different energy and carbon dioxide emission problems, which raise the question whether the industrial agglomeration promotes or inhibits energy efficiency and carbon dioxide emission. This paper explored the effects of the industrial agglomeration on carbon efficiency in China. Spatial econometric methods were implemented using panel data (2007–2016) of 285 cities above the prefecture level. The results revealed that industrial agglomerations have significant impacts on the urban carbon efficiency with significant spatial spillover effects. The agglomerations of the manufacturing and high-end productive service industries take positive effects on carbon efficiency while the low-end productive and living service industries take negative effects. As a comparison, we found that the agglomeration effects at the level of the megalopolis are greater than those at the national level, especially for the living services industry, in which the higher levels of agglomeration make the effects on carbon efficiency change from negative to positive. The divisions of labor for the central and common cities in the megalopolises are integrated into the industrial agglomeration. Furthermore, the fractional-order grey forecasting model is used in this paper. By the virtue of its advantage in dealing with small sample data which lack statistical rules, this paper makes an out-of-sample prediction of carbon efficiency and industrial agglomeration degree of Chinese cities. By adding the predicted results to the spatial correlation test, new evidence on the spatial correlation of carbon efficiency and spatial division of labor between cities is obtained. Based on the empirical results of the present study, we have proposed some policy recommendations.

The vertical profile of $C_n^2$ is the main factor for accurate astronomical observation and laser communication, however, hardware-based instruments and associated data are not widely available due to logistical and financial issues. In this article, we developed an indirect method, a hybrid network structure which is a combination of the backpropagation neural network and the simulated annealing algorithm, to fit the vertical profile of $C_n^2$. Radiosonde measurements from a field campaign over the Tibetan Plateau at Dachaidan (37.7○N, 95.3○E, 3180 m ASL) were performed in 2020 August to estimate the accuracy of our model, during which a balloon-borne portable turbulence meteorological radiosonde was used to measure the atmospheric optical profiles. Besides, the integrated astronomical parameters (the coherence length r0, seeing ε0, isoplanatic angle θ0, and the wavefront coherence time τ0), derived from $C_n^2$ and wind-speed vertical profiles, are investigated for astronomical applications using the proposed model. In addition, quantitative evaluations such as the correlation coefficient, the root mean squared error, and the systematic bias are used to quantify the performance of our model. More interesting, this model is found to outperform a widely used external scale model for the prevalent atmospheric conditions and shows better correlation and reliable estimates.

The synthesis of carbyne has remained an elusive goal for decades. One of the significant reasons is that high-purity and high-concentration hydrogen end-capped polyynes (C2nH2) as the most important model molecule and precursors for carbyne have been not widely prepared. Herein, we develop a facile and universal strategy to obtain high-purity and high-concentration C8-18H2 molecules using solid linear carbon chains with silver atom ending-capped (Ag2C8-18) as reaction precursors. The purified and concentrated C8-18H2 solution and Ag2C8-18 powder are evaluated by a combination of X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy, Raman spectroscopy, UV–vis–NIR spectroscopy and transmission electron microscope. These results confirm that the high-purity and high-concentration C2nH2 are obtained through the reaction of metal carbides solid and hydrogen chloride molecule. Our strategy for investigating unprotected linear carbon chains in solid and the successful preparation of high-concentration C2nH2 from solid carbides provide a new avenue for the research of linear carbon chains.

Microseismic (MS) event locations are vital aspect of MS monitoring technology used to delineate the damage zone inside the surrounding rock mass. However, complex geological conditions can impose significantly adverse effects on the final location results. To achieve a high-accuracy location in a complex cavern-containing structure, this study develops an MS location method using the fast marching method (FMM) with a second-order difference approach (FMM2). Based on the established velocity model with three-dimensional (3D) discrete grids, the realization of the MS location can be achieved by searching the minimum residual between the theoretical and actual first arrival times. Moreover, based on the calculation results of FMM2, the propagation paths from the MS sources to MS sensors can be obtained using the linear interpolation approach and the Runge–Kutta method. These methods were validated through a series of numerical experiments. In addition, our proposed method was applied to locate the recorded blasting and MS events that occurred during the excavation period of the underground caverns at the Houziyan hydropower station. The location results of the blasting activities show that our method can effectively reduce the location error compared with the results based on the uniform velocity model. Furthermore, the obtained MS location was verified through the occurrence of shotcrete fractures and spalling, and the monitoring results of the in-situ multipoint extensometer. Our proposed method can offer a more accurate rock fracture location and facilitate the delineation of damage zones inside the surrounding rock mass.

Bilayer graphene (BLG) grown via chemical vapor deposition (CVD) tends to exhibit twisted stacking. The twist angle θ t in twisted BLG (tBLG) provides a new degree of freedom for engineering its electronic and optical properties. In this paper, we investigate the θ t-dependent optical absorption in tBLG and deeply understand the electronic structure-optical properties correlations. New absorption peaks, whose wavelengths are modified by θ t, are observed on the feature of optical contrast (OC) in tBLG. Under the corresponding energy excitation, the Raman G mode in tBLG exhibits a significant enhancement. Furthermore, the results of θ t obtained by OC absorption peak are verified to be consistent with those by the Raman R mode. All these properties are proved to be related to the energy difference between low-energy Van Hove singularities (E VHS) in the density of states of tBLGs. This work builds a relation between optical absorption and twist angle, providing a viable method to identifying twist angles in tBLGs.

Structural reforms are currently the key way to achieve emissions reduction targets. A comprehensive investigation of the relationship between structural changes and carbon emissions is essential for further policy formulation. This paper aimed to discuss the impact of structural changes on per capita carbon emissions from the four aspects of energy, trade, society and economy, while considering the effects of economic growth and energy intensity. The ordinary least squares, fully modified ordinary least squares regression analysis and Granger causality test were used to analyze the situation of 147 countries and four income groups from 1990 to 2015. The results showed that at the global level, economic growth and economic structure were respectively the most significant positive and negative factors affecting carbon emissions. There was the bidirectional granger causality relationship between global per capita carbon emissions and economic growth, and between global per capita carbon emissions and economic structure. At the income group level, consistent with the global results, economic growth and energy intensity increase promoted the increase in carbon emissions, whereas increasing renewable energy consumption helped to reduce carbon emissions. The influence direction and degree of the remaining three factors differed among different income groups. In addition, the causal relationships among the variables of the income groups except the low income group were relatively complicated. Finally, policy recommendations were offered to reduce per-capita carbon emission through adjusting economic, energy, social, and trade structure.

Metal-rich chalcogenides with unique network architectures are rare but are of considerable interest because of their intriguing physical properties. In this work, a novel quaternary thioantimonate, Rb2CuSb7S12, has been discovered by a facile surfactant-thermal reaction. It crystallizes monoclinic space group P1 (No. 2) and exhibits a unique Sb-rich three-dimensional (3D) [CuSb7S12]2- framework surrounded by charge-compensating Rb+ cations. It is interesting to note that the Cu/Sb ratio of Rb2CuSb7S12 represents the lowest limit in the quaternary A/Cu/Sb/Q (A = alkali metals; Q = chalcogen) system. Moreover, Rb2CuSb7S12 shows rapid response and good reproducibility based on the photoelectrochemical tests. This study opens up opportunities for discovering the desirable physical properties in metal-rich chalcogenides.

Understanding the inconsistent rock fracture toughness (KIc) measurement results from different test specimen geometries helps provide suitable fracture parameters for engineering applications, predict rock fracture load, and assess the safety of flawed rock engineering structures. In this study, fracture experiments using full- or half-disc specimens with chevron notches or straight-through notches were conducted. Experimental results show that the notch types and loading methods (Brazilian-type diametric compression and three-point bending) significantly affect the KIc measurements. It is indicated that only considering the T-stress or fracture process zone (FPZ) alone cannot explain the test results well, while a good agreement is found between the experimental results and the interpretation based on the combined effects of T-stress and FPZ. Moreover, Brazilian-type compression and three-point bending under a short support span can make the full- or half-disc specimens have higher negative T-stress and larger FPZ, thus producing lower KIc values than three-point bending under a relatively long support span. Compared with KIc measurements using the straight-through notch specimens, those utilizing the chevron-notched ones are less affected by FPZ and yield higher KIc results, providing that the loading method is the same. The notch types have little impact on the T-stresses of the specimens. This study sheds light on the combined influence of T-stress and FPZ on rock fracturing.

PurposeThis study is aimed at better understanding the evolution of inequality in carbon emission in intraincome and interincome groups in the world, and then to uncover the driving factors that affect inequality in carbon emission.Design/methodology/approachThe approach is developed by combining the Theil index and the decomposition technique. Specifically, the Theil index is used to measure the inequality in carbon emissions from the perspective of global and each income group level. The extended logarithmic mean Divisia index was developed to explore the driving factors.FindingsThis study finds that the inequality in carbon emissions of intraincome group is getting better, whereas the inequality in carbon emission of interincome group is getting worse. And the difference in global carbon emissions between income groups is the main source of global carbon emission inequality, which is greater than that within each income group. In addition, the high-income group has transferred their carbon emissions to upper-middle income group by importing high-carbon-intensive products to meet the domestic demand, while lower-middle-income group do not fully participate in the international trade.Practical implicationsTo alleviate the global carbon inequality, more attention should be paid to the inequality in carbon emission of interincome group, especially the trade between high-income group and upper-middle income group. From the perspective of driving factors, the impact of import and export trade dependence on the per capita carbon emissions of different income groups can almost offset each other, so the trade surplus effect should be the focus of each group.Originality/valueIn order to consider the impact of international trade, this study conducts a comprehensive analysis of global carbon emissions inequality from the perspective of income levels and introduces the import and export dependence effect and the trade surplus effect into the analysis framework of global carbon emission inequality drivers, which has not been any research carried out so far. The results of this paper not only provide policy recommendations for mitigating global carbon emissions but also provide a new research perspective for subsequent inequality research.

The unique metal to insulator transition (MIT) of vanadium dioxide (VO2) makes it receiving extensive attention in the application of smart window. As for VO2-based smart window, the critical transition temperature (Tc) is required to be reduced to near room temperature for practical applications. In this paper, we fabricated VO2 films on ITO glass by hydrothermal method and applied voltage to ITO, therefore, the joule heat generated by ITO triggered the complete MIT of VO2 at room temperature in very short time ~3 s with applied voltage of 12 V. The VO2 film on ITO substrate shows obviously widened hysteresis behavior in the reversible transition process with a thermal hysteresis width of ~33 °C. The widened hysteresis loop makes it possible to stabilize the rutile phase (R) of VO2 at room temperature via applying a low holding voltage of 6 V. The proposed VO2/ITO film exhibits promising application in active smart window, and possesses advantages of simple structure, easy-fabricated and low-cost.

A cavitation bubble can be generated in polymer-cap on the fiber end-face by using femtosecond laser in less than 1 s. The position and diameter of the bubble can be adjusted by changing the focus position and average power of the laser beam, respectively. This efficient fabrication method was used to build cascaded Fabry–Perot interference cavities to increase the wavelength demodulation range. The evaluation method based on length matching analysis was proposed to obtain the optimized length of each cascaded cavity. Simulation results showed that the dominant peak/valley can always be highly distinguishable when the bubble diameter was located at $17.4\sim 21.5~\mu \text{m}$ . A larger fabrication tolerance was allowed and the manufacturing difficulty can be reduced tremendously. Finally, a sensor with a bubble diameter of about $20~\mu \text{m}$ was fabricated. Experimental results showed that the contrast of the dominant valley was increased to 20 dB, and the wavelength demodulation range of proposed sensor was nearly three times over that of the structure without bubble.

We have used simple time-shift analysis of diving waves to analyze shallow gas layers in a sedimentary overburden. By using simple equations for how the traveltime will change if a thin sand layer is charged by gas in a localized and constrained region, we show that such variations can be used to map and quantify the thickness of the gas layer. We use conventional 3D seismic data acquired close to a well where an unintended underground gas flow occurred in 1989. Raw seismic data are used as input, and time shifts are estimated for constant offsets for events that are interpreted as being predominantly diving waves. By assuming that the very shallow subsurface has a constant velocity gradient of [Formula: see text], we find diving wave time shifts that fit an average thickness of the gas layer of approximately 3–4 m. This is the minimum gas thickness because it is assumed that the time-shift analysis captures the diving wave hitting the top and the base of the gas layer (sufficiently dense offset sampling is important to achieve this). The outline and circumference of the close-to-circular gas anomaly around the well obtained by the diving wave analysis are confirmed by 3D reflection mapping of the same anomaly.

The improvement of the accuracy of simulated cloud-related variables, such as the cloud fraction, in global climate models (GCMs) is still a challenging problem in climate modeling. In this study, the influence of cloud microphysics schemes (one-moment versus two-moment schemes) and cloud overlap methods (observation-based versus a fixed vertical decorrelation length) on the simulated cloud fraction was assessed in the BCC_AGCM2.0_CUACE/Aero. Compared with the fixed decorrelation length method, the observation-based approach produced a significantly improved cloud fraction both globally and for four representative regions. The utilization of a two-moment cloud microphysics scheme, on the other hand, notably improved the simulated cloud fraction compared with the one-moment scheme; specifically, the relative bias in the global mean total cloud fraction decreased by 42.9%–84.8%. Furthermore, the total cloud fraction bias decreased by 6.6% in the boreal winter (DJF) and 1.64% in the boreal summer (JJA). Cloud radiative forcing globally and in the four regions improved by 0.3%−1.2% and 0.2%−2.0%, respectively. Thus, our results showed that the interaction between clouds and climate through microphysical and radiation processes is a key contributor to simulation uncertainty.

Two kinds of π-conjugated macrocycles with aggregation-induced emission (AIE) properties were investigated by scanning tunneling microscopy (STM) to elucidate their self-assembly behaviors and interaction with C60 on a highly oriented pyrolytic graphite (HOPG) surface. Both TPEMC and TPEMCS could self-assemble into orderly cavity structures. However, C60 guest molecules could only successfully enter the cavity of TPEMC to form a stable TPEMC + C60 host-guest coassembly structure. Density functional theory (DFT) calculations were also used to interpret the assembly mechanisms. This work disclosed the assembly characteristic of these new types of conjugated macrocyclic compounds, which was helpful to develop new structural porous luminescent materials.

Carbon nanobelts are molecules of high fundamental and technological interest due to their structural similarity to carbon nanotubes, of which they are molecular cutouts. Despite this attention, synthetic accessibility is a major obstacle, such that the few known strategies offer limited structural diversity, functionality, and scalability. To address this bottleneck, we have developed a new strategy that utilizes highly fused monomer units constructed via a site-selective [2 + 2 + 2] cycloaddition and a high-yielding zirconocene-mediated macrocyclization to achieve the synthesis of a new carbon nanobelt on large scale with the introduction of functional handles in the penultimate step. This nanobelt represents a diagonal cross section of an armchair carbon nanotube and consequently has a longitudinally extended structure with an aspect ratio of 1.6, the highest of any reported nanobelt. This elongated structure promotes solid-state packing into aligned columns that mimic the parent carbon nanotube and facilitates unprecedented host-guest chemistry with oligo-arylene guests in nonpolar solvents.

In high-speed impact loading experiments, localized deformation is readily taken place, which may result in differences in assessment of strain, strain rate, and further related deformation behaviors of a material in high rate deformations. In this paper, double-notch shear experiments of pure iron specimens were carried out by an improved split Hopkinson pressure bar (SHPB) device with impact speed ranging 16-64 m/s. The development of shear localization and fracture in shear deformation of the specimens was captured by a high-speed camera. Microstructures of localized shear band (LSB) in the shear zone of the specimens at different strain rate were analyzed by metallographic microscope. The nominal strain and strain rate in the deformation zone and the strain and strain rate in LSB were calculated based on the video frames and metallographic photomicrographs. Fracture strains of the shear bands at different impact speed were obtained. Results show that the deformation process of the specimens at different impact speeds includes uniform deformation, localized formation, microscopic crack, and macroscopic fracture; the formation of the LSB results in the decrease of the effective width of the shear band and causes the strain and strain rate to increase rapidly comparing with the nominal strain and strain rate.

With the rapid expansion of the natural gas consumption market worldwide, methanation of coal- or biomass-derived syngas for production of synthetic natural gas (SNG) is gaining considerable interest. In order to solve the problem of natural gas “peak shaving”, adjusting product distribution of the SNG plant is an efficient method to meet the demand fluctuation of natural gas in peak and off season. Herein, the conversion of syngas to SNG (CH4) and co-production of liquid fuels (C5+) over bimetallic Ni-Co catalysts was investigated at industrially relevant conditions. The effects of integration manner of the Ni-Co components, Ni/Co mass ratio, and the operating conditions on the catalytic performance were investigated. Due to the synergistic interaction between Ni and Co, silica supported Ni-Co bimetallic catalyst shows higher activity and total yield of methane and liquid fuels compared to the physically mixed sample. In addition, a good balance between Ni and Co content is crucial for the high efficiency co-production of SNG and liquid fuels. It is found that the optimum operating range in the present study is 550–578 K, H2/CO = 3, 3.0 MPa and W/F = 5 gcat h mol−1, in which more than 80 % total yield of methane and liquid fuels can be obtained on the 2Ni-1Co/SiO2 bimetallic catalyst. Moreover, it shows good thermal stability during the 55 h reaction time. All catalysts were examined by XRD, TEM, H2-TPR and XPS.

Electrocatalytic water splitting is a promising route for the generation of clean hydrogen. However, the anodic oxygen evolution reaction (OER) suffers greatly from low reaction kinetics and thereby hampers the energy efficiency of alkaline water electrolysers. In recent years, tremendous efforts have been dedicated to the pursuit of highly efficient, low cost and stable electrocatalysts for oxygen evolution reaction. Herein, an amorphous FeOOH roughened capillary-liked CoAl layered double hydroxide (LDH) catalyst grown on nickel foam (denoted as FeOOH–CoAl LDH/NF) was reported for OER electrolysis. The developed FeOOH–CoAl LDH/NF electrode shows excellent OER activity with overpotentials of 228 mV and 250 mV to deliver a current density of 50 mA cm−2 and 100 mA cm−2 in 1.0 M KOH solution, respectively, ranking it one of the most promising OER catalysts based on transition-metal-based LDH. This is owed to the formed capillary-liked hierarchy structure with high-porosity as well as the strong electronic interaction between FeOOH and CoAl LDH. The developed morphological engineering approach to build hierarchal porous structures together with facile amorphous FeOOH modification may be extended to other layered double hydroxide catalyst for enhanced OER activities.

G-quadruplexes (G4s) are prevalent in oncogenes and proposed to be potential antitumor drug targets. However, binding selectivity of compounds to G4s still faces challenges. Herein, we report a platinum(II) complex ( Pt1 ), whose affinity to G4-DNA is activated by adaptive binding and selectivity controlled by binding kinetics. The resolved structure of Pt1 /VEGF-G4 (a promoter G4) reveals that Pt1 matches 3'-G-tetrad of VEGF-G4 through Cl - -dissociation and loop rearrangement of VEGF-G4. Binding rate constants are determined by coordination bond breakage/formation and correlate fully with affinities. The selective rate-determining binding step, Cl - -dissociation upon G4-binding which is 2~3 orders of magnitude higher than dsDNA. We further demonstrate that Pt1 potently targets G4 in living cells, effectively represses VEGF expression and inhibits vascular growth in zebrafish. We present adaptive G4-binding activation and selectivity controlled by kinetics, providing a complementary design principle for compounds targeting G4 or similar biomolecules.

In order to improve the energy level of fuel air explosive(FAE) with delayed secondary igniters, high energetic metal powders were added to liquid fuels mainly composed of ether and isopropyl nitrate. Metal powders’ explosive properties and reaction mechanisms in FAE were studied by high-speed video, pressure test system, and infrared thermal imager. The results show that compared with pure liquid fuels, the shock wave overpressure, maximum surface fireball temperature and high temperature duration of the mixture were significantly increased after adding high energetic metal powder. The overpressure values of the liquid-solid mixture at all measuring points were higher than that of the pure liquid fuels. And the maximum temperature of the fireball was up to 1700 °C, which was higher than that of the pure liquid fuels. After replacing 30% of aluminum powder with boron or magnesium hydride, the shock wave pressure of the mixture was further increased. The high heat of combustion of boron and the hydrogen released by magnesium hydride could effectively increase the blast effect of the mixture. The improvement of the explosion performance of boron was better than magnesium hydride. It shows that adding high energetic metal powder to liquid fuels can effectively improve the explosion performance of FAE.

Two-dimensional (2D) organic-inorganic hybrid perovskites, benefiting from their natural anisotropy of quantum-well motifs and optical properties, have shown remarkable polarization-dependent responses superior to the 3D counterparts. Here, for the first time, multiwavelength polarization-sensitive detectors were fabricated by using single crystals of a guanidine-based 2D hybrid perovskite, (BA)2 (GA)Pb2 I7 (where BA+ is n-butylammonium and GA+ is guanidium). Its unique 2D quantum-well structure results in strong crystallographic-dependence of optical absorption. Strikingly, our crystal-based photodetector exhibits a prominent photocurrent dichroic ratio (Imax /Imin ) of ∼2.2 at 520 nm, higher than the typical 2D inorganic materials (GeSe, ∼1.09, PdSe2 , ∼1.8). In addition, notable dichroic ratios of 1.29 and 1.23 at 405 nm and 637 nm are also created for the multiwavelength polarized-light detection. The prominent detecting performances, including low dark current (1.6×10-11 A), considerable on/off ratio (∼2×103 ), high photodetectivity (∼3.3×1011 Jones) and responsivity (∼12.01 mA W-1 ), make (BA)2 (GA)Pb2 I7 a promising candidate for polarized-light detection. This work sheds light on the rational engineering of new 2D hybrid perovskites for the high-performance optoelectronic device applications.

Ferroptosis regulates cell death through reactive oxygen species (ROS)-associated lipid peroxide accumulation, which is expected to affect the structure and polarity of lipid droplets (LDs), but with no clear evidence. Herein, we report the first example of an LD/nucleus dual-targeted ratiometric fluorescent probe, CQPP, for monitoring polarity changes in the cellular microenvironment. Due to the donor-acceptor structure of CQPP, it offers ratiometric fluorescence emission and fluorescence lifetime signals that reflect polarity variations. Using nucleus imaging as a reference, CQPP was applied to report the increase in LD polarity and the homogenization of polarity between LDs and cytoplasm in the ferroptosis model. This LD/nucleus dual-targeted fluorescent probe shows the great potential of using fluorescence imaging to study ferroptosis and ferroptosis-related diseases.

The electrocatalytic oxygen evolution reaction from H2O (OER) is essential in a number of areas like electrocatalytic hydrogen production from H2O. A Ni oxyhydroxide nanosheet (NiNS) is among the most widely studied OER catalysts but still suffers from low activity, sluggish kinetics, and poor stability. Herein, we incorporate MoO3 patches into NiNS to form a nanosheet with an intimate Ni-Mo interface (NiMoNS) for the OER. The overpotential at 10 mA cm-2 and Tafel slope on NiMoNS (260 mV, 54.7 mV dec-1) are lower than those on NiNS (296 mV, 89.3 mV dec-1), implying that higher activity and faster kinetics are achieved on NiMoNS. There is no change in electrocatalytic efficiency of NiMoNS after 18 h of OER, but the electrocatalytic efficiency of NiNS decreases by 56% after only 8 h of OER. Thus, NiMoNS has better stability. The intimate Ni-Mo interface promotes two-dimensional lateral growth of NiMoNS to form a surface area 1.5 times larger than that of NiNS, and facilitates electron transfer from Ni to Mo. This makes the Ni3+/Ni2+ ratio on the NiMoNS surface (1.32) higher than that on the NiNS surface (0.68). Moreover, the Ni3+/Ni2+ ratio on NiMoNS surface increases to 1.81 after 18 h of OER but the Ni3+/Ni2+ ratio on the NiNS surface decreases to 0.51 after 8 h of OER. Therefore, the NiMoNS surface has more abundant and stable Ni3+ sites which are catalytically active toward OER. This could be the reason for the enhanced activity, kinetics, and stability of NiMoNS. The results are very valuable for fabricating more efficient catalysts for electrocatalysis.

In this paper, we simulate the electrical characteristics of the n-type metal-oxide-semiconductor (NMOS) transistor in a 65-nm complementary metal-oxide-semiconductor (CMOS) inverter under the actions of heavy ions with different linear energy transfers (LET). We analyze the influence of incident ions with different LETs on a device using technology computer-aided design (TCAD) software, and aim to establish an HSPICE sub-circuit model containing the relationship between the electrical properties of a device and the LET of an incident ion for circuit-level HSPICE simulation. Based on the SEE funnel mechanism, we propose an analytical model to describe the relationship between the charge collected by the NMOS drain and the LET of the incident ion, and build an HSPICE model based on this analytical model. With such a model, the influence of incident ions with different circuit-level LETs can be determined from HSPICE simulation. In addition, good agreement with simulation results is reached, proving the reasonableness of the proposed model.

As a part of the earthquake ground motion, large velocity pulses are probably one of the important factors leading to serious rock structural damage and geological disasters. It is vitally important to identify the response characteristics of large-scale structures under near-field pulse-like ground motions for earthquake prevention and disaster reduction. In this study, the pulse parameters from the 1999 Chi-Chi and 2018 Hualien earthquakes are extracted using the wavelet transform method, and the potential consequences of velocity pulses on the seismic response of the buildings are assessed. Our results show that the near-field ground motions affected by the directivity effect contain some rich large pulse contents in the velocity time histories. The Chi-Chi earthquake presents a more obvious directivity effect than the Hualien earthquake, and the near-field velocity pulses are closely related to the severely damaged structures. The potential damage of both earthquakes to high-rise buildings can be evaluated by the relationship between the characteristic period of the velocity pulse and the fundamental natural period of the engineering structure. By comparing the periods, it can be revealed that some long-period spectral values in the range of 0.8–3.0 s exceed the seismic design values in the vicinity of the causative faults, and the vulnerability of high-rise buildings against pulse-like ground motions in the Chi-Chi earthquake is stronger than that in the Hualien earthquake. Interestingly, the ratio of peak ground velocity to acceleration (PGV/PGA) and maximum pseudo response velocity (PSV) are suitable as seismic intensity indicators of pulse-like ground motions, which can reflect the rupture direction of source characteristic and site amplification of near-surface soft deposition area around the causative fault. This study provides some references for seismic hazard assessment and post-earthquake structural design.

Electrical energy storage (EES) systems consisting of multiple process components and containing intensive amounts of energy present inherent hazards coupled with high operational risks. Although the thermal hazards of batteries have aroused widespread attention, the safety issues of emerging large scale EES technologies persist. This study aims to begin to fill this gap by examining the hazards of typical 100 MWh or more EES systems which are used for grid applications. These systems include compressed and liquid air energy storage, CO2 energy storage, thermal storage in concentrating solar power plants, and Power-to-Gas. Hazard assessments are performed using a hybrid method to consider and evaluate the EES systems’ potential hazards from three novel aspects: storage, operability, and connectivity. Results reveal that for a similar energy storage capacity, cryogenic liquid systems have the least severe accident consequences while thermal energy storage using synthetic oil exhibits the largest. Concerning the operations in many cases, extreme operating conditions, complicated heat exchanger networks involving multiple flammable working fluids, and system operation intermittency present the major challenges to the safer operation of EES systems. Lastly, these systems themselves form one of many components of the power supply, each of which needs to accommodate fluctuations in supply and demand but also should be prevented from transmitting hazards to each other. Considering both engineering and administrative controls, this paper concludes with a discussion on the four grouped strategies from inherent to procedural for the elimination and mitigation of the identified hazards. Representative solutions and research perspectives including inherently safer design, operation uncertainty management, resilience analysis, energy barriers design, and life cycle safety assessment are suggested for the overall safety enhancement of industrial EES systems.

Rationale: Precise treatment of tumors is attracting increasing attention. Molecular probes simultaneously demonstrating the diagnostic signal and pharmacological effect in response to tumor microenvironment are highly desired. γ-glutamyl transpeptidase (GGT) is a biomarker with significantly up-regulated expression in the tumor area. We developed a GGT responsive near-infrared (NIR) nanoassembly for tumor-specific fluorescence imaging-guided photothermal therapy. Methods: The GGT responsive NIR probe was constructed by conjugating GGT-specific substrate γ-glutamic acid (γ-Glu) with cyanine fluorophore (NRh-NH2) via amide reaction. The resulting NRh-G spontaneously assembled into nanoparticles (NRh-G-NPs) around 50 nm. The NPs were characterized and the properties evaluated in the presence or absence of GGT. Subsequently, we studied fluorescence imaging and photothermal therapy of NRh-G-NPs in vitro and in vivo. Results: NRh-G-NPs, upon specific reaction with GGT, turned into NRh-NH2-NPs, showing a ~180-fold fluorescence enhancement and excellent photothermal effect recovery. NRh-G-NPs could selectively light up U87MG tumor cells while their fluorescence was weak in L02 human normal liver cells. The NPs also showed excellent tumor cell ablation upon laser irradiation. After intravenous injection into tumor-bearing mice, NRh-G-NPs could arrive in the tumor area and specifically light up the tumor. Following laser irradiation, the tumor could be completely erased with no tumor reoccurrence for up to 40 days. Conclusions: NRh-G-NPs were specifically responsive to GGT overexpressed in U87MG tumor cells and selectively lit up the tumor for imaging-guided therapy. Besides, the recovery of photothermal property in the tumor area could improve cancer therapy precision and decreased side effects in normal tissues.

Transition-metal sulfides (TMSs) were demonstrated to be heartening anodes for sodium-ion batteries (SIBs) because of their alterable nanostructures, large theoretical capacity and environmental friendliness. Whereas, the relatively poor rate and cycling capability of TMSs still hinder the rapid development of their practical applications. Herein, a novel CuS nanocable self-assembled by hierarchical nanosheet is designed as SIB anodes, which delivers a large capacity (367 mAh g−1 at 5 A g−1), excellent rate capacity and cycle performance (213 mAh g−1 after 2000 cycles at 15 A g−1). The uniquely hierarchical nanostructure can both contribute more effective and durable active sites and shorter diffusion length of sodium ions/electrons. Besides, ex situ XRD, HRTEM and SAED reveal the phase transformation during sodiation process and the reaction mechanism of as-synthesized CuS nanocables. These results can offer new clues and inspirations to understand the relationship between the designed nanostructures and sodium storage behaviors of other TMSs.

The strengthening method of multi-element M-site solid solution is a common approach to improve mechanical properties of MAX phase ceramic. However, the research on capability of multi-element A-site solid solution to improve mechanical properties has rarely been reported. Thereupon, quasi-high-entropy MAX phase ceramic bulks of Ti2(Al1−xAx)C and Ti3(Al1−xAx)C2 (A = Ga, In, Sn, x = 0.2, 0.3, 0.4) were successfully synthesized by in situ vacuum hot pressing via multi-elements solid solution. The multi-elements solid solution in single-atom thick A layer was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy as well as by energy dispersive X-ray spectroscopy mappings. Effects of doped multi-elements contents on the phase, microstructure, mechanical properties, and high temperature tribological behaviors were studied. Results demonstrated that the Vickers hardness, anisotropic flexural strength, fracture toughness, and tribological properties of Ti–Al–C based MAX ceramics could be remarkably improved by constitution of quasi-high-entropy MAX phase in A layers. Moreover, the strengthening and wear mechanisms were also discussed in detail. This method of multi-element solid solution at A-site provides new way to enhance mechanical properties of other MAX phase ceramics.

Background Forage production is the fundamental ecosystem service of grasslands. Although forage consumption occurs at community level, most studies focused on species-level changes of forage quality. The quantitative and qualitative changes of forage production are driven by species-specific trait, intra-specific plasticity, and species turnover. We examined the changes in forage production and digestibility after 5-year factorial treatments of nitrogen (N) addition and mowing in a temperate steppe and linked such changes to community assembly under the Price equation framework. Results Nitrogen addition significantly reduced species richness, increased forage production, but did not change forage digestibility (indicated by the total Ca+Mg concentrations). Mowing did not affect forage production and digestibility. The positive effects of N addition on forage production were driven by the enhancement of abundance of the remaining species following N enrichment, rather than by species loss or species gain. The species identity effects could offset the effects of species richness loss or gain on forage production and digestibility. Conclusions Our results highlight the importance of a community perspective in addressing the quantitative and qualitative changes of forage production under global change pressure of N enrichment. Species identity is important in determining the contribution of different processes of community assembly to ecosystem services.

There continues to be debate regarding the timing of the collision between the Indian and Eurasian plates and the uplift of the Tibetan Plateau. This study presents zircon U–Pb geochronology, whole-rock geochemistry, and Lu–Hf isotopic data for the Saiduopugangri granite of the Qiangtang Terrane, located within the core of the Tibetan Plateau. These data provide the basis for the geodynamic setting, petrogenesis, and characteristics of its magma source. Zircons from the Saiduopugangri granite yield a weighted-mean 206Pb/238U age of 62.72 ± 0.06 Ma, indicating that these rocks formed during the early Palaeocene. The rocks are members of the highly calc-alkaline to shoshonitic series, with weak peraluminous characteristics. Trace elements are characterised by high Sr (483–616 ppm), and low Y (6–10 ppm) and Yb (1 ppm) content, typical of a high Sr and low Yb granite. The εHf(t) of zircon ranges from −2.14 to 2.35, with two-stage Hf model ages (TDM2) ranging from 1182 to 895 Ma. These data suggest that the Saiduopugangri granite magma was derived from the melting of lower-crustal clastic meta-sedimentary rocks and mantle-derived basalts. The high Sr and low Yb granite characteristics and experimental results indicate that melting occurred at >1.2 GPa and >750 °C, consistent with a crustal thickness greater than 50 km. Magmatism occurred from the Late Cretaceous to the early Palaeogene and is broadly synchronous with the collision timing between the Indian and Eurasian plates. The Saiduopugangri granite provides evidence of crustal thickening of the Tibetan Plateau and its age and petrogenesis constrain the timing of the initial uplift.

The development of Ni-based single crystal superalloys relies heavily on the composition design with the addition of critical alloying elements, e.g., Re and Ru. Understanding the role of alloying effects require to know the configurations of the alloying element distribution between γ-Ni and γ′-Ni3Al phases and among various non-equivalent sites. This work employed first-principles density functional theory calculations to study the preference of phase and site occupancy of 11 alloying elements including Al and transition metal elements: 3d (Ti, Cr, Co, Ni), 4d (Mo, Ru), and 5d (Hf, Ta, W, Re) in Ni and Ni3Al. We calculated the substitution energies of 1298 triple-site doping configurations including 286 NiNiNi site doping of Ni, 726 AlNiNi site doping, and 286 NiNiNi site doping of Ni3Al with alloying elements Ni, Co, Ru, Cr, Re, Mo, W, Al, Ti, Ta, and Hf. In the dual-site and triple-site doping of Ni and Ni3Al, all studied alloying elements preferred to occupy Ni phase rather than Ni3Al phase. We found that the most stable defect complexes often contained the favorable substitutions of Al, Ti, Ta, and Hf for the Ni sites that stabilized the alloying elements doping at the other one or two nearest neighbor sites. The co-substitutions of various alloying elements at multiple sites are critical to understanding the strengthening mechanism of alloying elements in Ni-based single crystal superalloys.

With the global economy increasingly dependent on innovation, urban discourse has shifted to consider what kinds of spatial designs may best nurture innovation. We examined the relationship between the built environment and the spatial heterogeneity of regional innovation productivity (RIP) using the example of China’s Pearl River Delta (PRD). Based on a spatial database of 522 546 patent data from 2017, this study proposed an innovation-based built environment framework with the following five aspects: healthy environment, daily interaction, mixed land use, commuting convenience, and technology atmosphere. Combining negative binomial regression and Geodetector to examine the impact of the built environment on RIP, the results show that the spatial distribution of innovation productivity in the PRD region is extremely uneven. The negative binomial regression results show that the built environment has a significant impact on the spatial differentiation of RIP, and, specifically, that healthy environment, mixed land use, commuting convenience, and technology atmosphere all demonstrate significant positive impacts. Meanwhile, the Geodetector results show that the built environment factor impacts the spatial heterogeneity of RIP to varying degrees, with technology atmosphere demonstrating the greatest impact intensity. We conclude that as regional development discourse shifts focus to the knowledge and innovation economy, the innovation-oriented design and updating of built environments will become extremely important to policymakers.

As a typical halophilic bacterium, Vibrio parahaemolyticus (V. parahaemolyticus) is regarded as one of the marine seafood-borne pathogens causing severe illnesses in humans and aquatic animals. Herein, a novel single primer isothermal amplification (SPIA) technique which was modified with SYBR Green II was successfully developed for the visual detection of V. parahaemolyticus. Interestingly, the visual superiority of SPIA can be achieved by fluorescence or precipitate to analyze the target pathogens in the seafood samples. The experimental results showed that all of V. parahaemolyticus strains were positive by using the novel SPIA assay, whereas the non-V. parahaemolyticus counterparts were negative. Furthermore, the limit of detection (LOD) of the SPIA assay was 5.7 CFU/mL in pure culture and 42 CFU/g in raw oysters by the visual fluorescence, respectively. Compared with the standard method, the developed SPIA approach achieved the satisfactory results with the characteristics of 100% sensitivity, 98.21% specificity, and 99.17% accuracy in the detection of 241 seafood samples. The developed SPIA method has been demonstrated as a rapid, specific, sensitive, and visual tool for the detection of V. parahaemolyticus, which could be adopted for routine surveillance of food-borne pathogens in the seafood samples.

A versatile microporous metal-organic framework (MOF), {[Cu(TIA)]·1.5CH3OH}n (Cu-1), was successfully obtained via the solvothermal reaction of cuprous(II) salt with the bifunctional ligand 3-(1H-1,2,4-triazol-1-yl)isophthalic acid. Single-crystal X-ray diffraction studies indicate that Cu-1 contains an apo three-dimensional skeleton and two types of one-dimensional channels. The framework of Cu-1 has excellent acid-alkali resistance and thermal stability, which is stable in a pH = 2-13 aqueous solution and an 260 °C air environment. In addition, the microporous copper MOF shows very high uptakes of CO2 (180 cm3·g-1) and C2H2 (113 cm3·g-1) at 273 K and displays excellent adsorption selectivity for small molecular gases. The ideal adsorbed solution theory selectivity values for C2H2/C2H4, CO2/CH4, and CO2/N2 are 2, 9, and 22 at 298 K, respectively. At the same time, breakthrough experiments for CO2/CH4, CO2/N2, and C2H2/C2H4 were further conducted to verify the efficient separation performances.

The production, consumption, and waste of plastics have been rapidly growing worldwide in the last decades. A variety of data are needed to characterize plastics stocks and flows across space, time, and life cycle to derive insights for developing strategies to address various sustainability challenges from plastics and plastics waste. Here we review data sources on plastics stocks and flows to identify data gaps and research needs. We categorize the reviewed data sources by life cycle stages of plastics including material production, semi‐manufacturing, manufacturing, additives, consumption, in‐use stock, end‐of‐life, waste treatment, and trade. We identify four data gaps in these existing data for characterizing plastics stocks and flows, including inconsistent classification, missing data, conflicting data, and inexplicit data for plastics products and waste. These data gaps represent critical research needs including common platform for data sharing, standard methods for data reconciliation and estimation, consistent data collection and reporting, and new approaches for data collection and curation. This review establishes the state‐of‐the‐art of plastics stock and flow data and develops a roadmap for a high‐quality, comprehensive characterization of plastics stocks and flows to develop management strategies to address the sustainability challenges of plastics production, consumption, waste, and pollution.

Few problems in statistics are as perplexing as variable selection in the presence of very many redundant covariates. The variable selection problem is most familiar in parametric environments such as the linear model or additive variants thereof. In this work, we abandon the linear model framework, which can be quite detrimental when the covariates impact the outcome in a non-linear way, and turn to tree-based methods for variable selection. Such variable screening is traditionally done by pruning down large trees or by ranking variables based on some importance measure. Despite heavily used in practice, these ad hoc selection rules are not yet well understood from a theoretical point of view. In this work, we devise a Bayesian tree-based probabilistic method and show that it is consistent for variable selection when the regression surface is a smooth mix of p > n covariates. These results are the first model selection consistency results for Bayesian forest priors. Probabilistic assessment of variable importance is made feasible by a spike-and-slab wrapper around sum-of-trees priors. Sampling from posterior distributions over trees is inherently very difficult. As an alternative to Markov Chain Monte Carlo (MCMC), we propose approximate Bayesian computation (ABC) Bayesian forests, a new ABC sampling method based on data-splitting that achieves higher ABC acceptance rate. We show that the method is robust and successful at finding variables with high marginal inclusion probabilities. Our ABC algorithm provides a new avenue towards approximating the median probability model in non-parametric setups where the marginal likelihood is intractable.

BACKGROUND: Odorant‐binding proteins (OBPs) in insects contribute to the sensitivity of the olfactory system and connect external odorants to olfactory receptor neurons. Determination of the chemosensory functions in Diaphorina citri, a vector of the citrus Huanglongbing pathogen, may help in developing a potential target for pest management. RESULTS: Diaphorina citri showed dose‐dependent electroantennogram recording (EAG) responses to 12 host plant volatiles. A two‐choice behavioral trap experiment showed that four compounds (methyl salicylate, linalool, citral and R‐(+)‐limonene) that elicited high EAG responses also had significant attraction to adults. The expression profiles induced by these compounds were detected in nine OBP genes, DcitOBP1–9. DcitOBP3, DcitOBP6 and DcitOBP7 commonly showed significant upregulation or downregulation compared with the control. Microscale thermophoresis (MST) showed that the recombinant protein DcitOBP7 had high in vitro binding affinities (Kd

This article proposes a rotor position observer based on a reactive power model reference adaptive system (MRAS) for sensorless direct voltage control (DVC) strategy of the stand-alone brushless doubly fed induction generators (BDFIGs). The proposed MRAS observer is based on the control winding (CW) reactive power and the power winding (PW) field orientation. The suggested new sensorless control method does not require flux computation, which can ensure the simplicity and efficacy of the proposed method. The stability analysis of the new observer is investigated and confirmed with the concept of hyperstability and using Popov’s criterion methodology. The robustness of the new control method is analyzed under parameter uncertainties. Furthermore, comprehensive simulation and experimental results are obtained with a prototype wound-rotor BDFIG. The corresponding results confirm the capability and effectiveness of the proposed sensorless DVC strategy with a good transient behavior under different operating conditions for the stand-alone BDFIG system. Moreover, these results assure that the presented rotor position observer is robust via any machine parameter change.