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The low O2activation ability at low temperatures and SO2poisoning are challenges for metal oxide catalysts in the application of Hg0removal in flue gas. A novel high-entropy fluorite oxide (MgAlMnCo)CeO2(Co-HEO) with the second phase of spinel is synthesized by the microwave hydrothermal method for the first time. A high efficiency of Hg0removal (close to 100%) is achieved by Co-HEO catalytic oxidation at temperatures as low as 100 °C and in the atmosphere of 145 μg m–3Hg0at a high GHSV (gas hourly space velocity) of 95,000 h–1. According to O2-TPD and in situ FT-IR, this extremely superior catalytic oxidation performance at low temperatures originates from the activation ability of Co-HEO to transform O2into superoxide and peroxide, which is promoted by point defects induced from the spinel/fluorite heterointerfaces. Meanwhile, SO2resistance of Co-HEO for Hg0removal is also improved up to 2000 ppm due to the high-entropy-stabilized structure, construction of heterointerfaces, and synergistic effect of the multicomponents for inhibiting the oxidation of SO2to surface sulfate. The design strategy of the dual-phase high-entropy material launches a new route for metal oxides in the application of catalytic oxidation and SO2resistance.

The presence of structural planes in rock masses reduces their mechanical properties and greatly affects their failure mode, resulting in physical and mechanical anisotropy. This study investigated the mechanical behaviors and damage characteristics of excavated jointed rocks in three-dimensional (3D) printed structures. A digital fracture network model based on the fractal principle was also developed to simulate a complex and rough network of fractures. Using 3D printing technology, rock specimens within a single rough structure surface, different dip angles, and rough fracture network models were established, considering different excavation sizes. Uniaxial compression was performed experimentally to investigate the mechanical response of rock masses. The failure processes of the jointed specimens were analyzed based on the digital image correlation (DIC) technique. The uniaxial compressive strength and elastic modulus were compared considering different excavation sizes. The results show that the geometric characteristics of the joints significantly influence the strength and failure mode of the rock mass. The strength of the layered rock mass shows a significant linear correlation with increasing excavation sizes. This research could provide a reference for studying the mechanical behavior of jointed rock masses using 3D printing technology.

Transition metal sulfides have exhibited remarkable advantages in gaseous elemental mercury (Hg0) capture under high SO2atmosphere, whereas the weak thermal stability significantly inhibits their practical application. Herein, a novel N,N-dimethylformamide (DMF) insertion strategy via crystal growth engineering was developed to successfully enhance the Hg0capture ability of MoS2at an elevated temperature for the first time. The DMF-inserted MoS2possesses an edge-enriched structure and an expanded interlayer spacing (9.8 Å) and can maintain structural stability at a temperature as high as 272 °C. The saturated Hg0adsorption capacities of the DMF-inserted MoS2were measured to be 46.91 mg·g–1at 80 °C and 27.40 mg·g–1at 160 °C under high SO2atmosphere. The inserted DMF molecules chemically bond with MoS2, which prevents possible structural collapse at a high temperature. The strong interaction of DMF with MoS2nanosheets facilitates the growth of abundant defects and edge sites and enhances the formation of Mo5+/Mo6+and S22–species, thereby improving the Hg0capture activity at a wide temperature range. Particularly, Mo atoms on the (100) plane represent the strongest active sites for Hg0oxidation and adsorption. The molecule insertion strategy developed in this work provides new insights into the engineering of advanced environmental materials.

This study investigates the cloud macro- and micro-physical characteristics in the convective and stratiform regions and their different responses to the seeding for mixed convective-stratiform clouds that occurred in Shandong province on 21 May 2018, based on the observations from the aircraft, the Suomi National Polar-Orbiting Partnership (NPP) satellite, and the high-resolution Himawari-8 (H8) satellite. The aircraft observations show that convection was deeper and radar echoes were significantly enhanced with higher tops in response to seeding in the convective region. This is linked with the conversion of supercooled liquid droplets to ice crystals with released latent heat, resulting in strengthened updrafts, enhanced radar echoes, higher cloud tops, and more and larger precipitation particles. In contrast, in the stratiform cloud region, after the Silver Iodide (AgI) seeding, the radar echoes become significantly weaker at heights close to the seeding layer, with the echo tops lowered by 1.4–1.7 km. In addition, a hollow structure appears at the height of 6.2–7.8 km with a depth of about 1.6 km and a diameter of about 5.5 km, and features such as icing seeding tracks appear. These suggest that the transformation between droplets and ice particles was accelerated by the seeding in the stratiform part. The NPP and H8 satellites also show that convective activity was stronger in the convective region after seeding; while in the stratiform region, a cloud seeding track with a width of 1–3 km appears 10 km downstream of the seeding layer 15 minutes after the AgI seeding, which moves along the wind direction as width increases.

Reflectivity, one of the most key specifications for display, is pursued to be extreme low to match the name of ultimate display for micro-LEDs. Conventionally, black light shield film is fabricated by photolithographic process before or after the micro- LED chips being mass transferred to the driver substrate to meet this requirement. In this study, we report a novel black light shield film material by a simple and effective graphical process to achieve ultra-low reflectivity with little influence on the light output of LED chips to dispense with complicated lithography process, which can fill the gap between the LED chips and the eutectic layer at the bottom of the LED chips, and expose the top of the micro-LED chips simultaneously. The black light shield film was directly adhered to the micro-LED substrate by heating, vacuum and press. Whole surface ashing process was then carried out to remove the excess black light shield film on the surface of the micro-LED substrate. By optimizing the thickness of removed black film, the surface of the micro-LED chips could be exposed while other places were still covered with black light shield film. A full-color Micro-LED display with 114 PPI resolution and size of 1.98-inch was successfully fabricated and showed superb performance with 1.16% reflectivity.

Graphical Abstract:

Opioids, such as morphine, are clinic analgesics which induce euphoria. Morphine exposure modifies the excitability and functional interactions between neurons, while the underlying cellular and molecular mechanisms, especially how morphine assembles heterogeneous interneurons (INs) in prelimbic cortex (PrL) to mediate disinhibition and reward, are not clear. Using approaches of optogenetics, electrophysiology, and cell type-specific RNA-seq, we show that morphine attenuates the inhibitory synaptic transmission from parvalbumin+(PV)-INs onto pyramidal neurons in PrL via μ-opioid receptor (MOR) in PV-INs. Meanwhile, morphine enhances the inhibitory inputs from somatostatin+(SST)-INs onto PV-INs, and thus disinhibits pyramidal neurons via δ-opioid receptor (DOR)-dependent Rac1 upregulation in SST-INs. We show that MOR in PV-INs is required for morphine-induced behavioral sensitization, while DOR as well as Rac1 activity in SST-INs is required for morphine-induced conditioned place preference and hyper-locomotion. These results reveal that SST- and PV-INs, functioning in PrL as a disinhibitory architecture, are coordinated by morphine via different opioid receptors to disinhibit pyramidal neurons and enhance reward.

In electrochemistry, the carbazole is generally coupled to dimer but not to polymer. This work has reported that organic electropolymerization (OEP) of 4,4′,4″-tri(N-carbazolyl)triphenylamine (TCTA) would form a high cross-linked carbazole polymer by its high activity/reversibility and a synchronous viscosity control. It has significantly improved the OEP film quality of both hole-transporting and electroluminescent layers in organic light-emitting diodes. As a result, the conductivity and power efficiency of the organic light-emitting diodes with TCTA are eight and four times of that without TCTA. A prototype display device with a 1.7 in. monochrome passive matrix of 58 ppi under the driving chip is successfully fabricated with accurate pixel size and uniform electroluminescence, which shows a great potential of OEP in the electroluminescent application.

Elemental mercury (Hg0) emission is a well-known environmental issue in traditional coal-combustion power plants. Now, enhancing Hg0oxidation in the selective catalytic reduction of the NOxunit is a promising strategy to reduce mercury pollution. In this study, CuAlO2catalyst was engaged in Hg0oxidation for the first time. The CuAlO2catalyst exhibited more remarkable Hg0catalytic oxidation ability than commercial SCR catalysts and self-made V2O5-WO3/TiO2. The Hg0oxidation efficiencies over the CuAlO2catalyst were above 89.6 and 97.9% in SCR and SFG atmospheres at 300 °C, respectively. The effects of flue gas components over the CuAlO2catalyst were studied systematically for Hg0oxidation. The co-presence of NO and O2could generate active nitrogen oxide species over the CuAlO2catalyst to promote the Hg0oxidation. HCl played a crucial role in high-efficiency Hg0oxidation due to the activation of chlorine on the CuAlO2surface. NH3, SO2, and H2O inhibited Hg0conversion by occupying the active sites or consuming active chlorine species. However, the suppression effect of NH3, SO2, and H2O would be eclipsed by appropriately decreasing reaction GHSV (gas hourly space velocity), adding NO, and increasing HCl concentration, respectively. Furthermore, the mechanism of Hg0oxidation over CuAlO2followed the Deacon reaction and partial Deacon reaction mechanism according to Y-tube experiment and XPS (X-ray photoelectron spectroscopy) analysis. This work provided the basic data regarding industrial applications of novel CuAlO2catalysts and was significant for further improving its Hg0oxidation activity.

The thin-film transistor (TFT) driving circuit is a separate electronic component embedded within the panel itself to switch the current for each pixel in active-matrix organic light-emitting diode displays. We reported a TFT-directed dye electroplating method to fabricate pixels; this would be a new method to deposit films on prepatterned electrode for organic full-color display, where TFT driving circuit provide a switching current signal to drive and direct dye depositing on selected RGB pixels. A prototype patterned color pixel matrix was achieved, as high-quality light-emitting films with uniform morphology, pure RGB chromaticity, and stable output.

Recently, the Hg0re-emission from flue scrubbing solutions has become a research focus. The objective of this study was to evaluate the influence of arsenite on Hg0re-emission by investigating critical important parameters, including the arsenite ion concentration, pH values, solution temperature, fluorine ion concentration, and chlorine ion concentration. The experimental results indicate that arsenite could directly reduce Hg2+to Hg0and promote the decomposition of Hg(SO3)22–. High pH, temperature, and chlorine ion concentration contributed to the inhibition of Hg0re-emission, but the fluorine ions had little effect. The mechanism research suggests that the formation of unstable HgH2AsO3+at low arsenite concentration accelerates Hg0re-emission. For the Hg(II)–As(III)–S(VI) system, the formation of unstable HgSO3H2AsO3–than Hg(SO3)22–could increase Hg0re-emission. With an increase in arsenite concentration, the formation of Hg(H2AsO3)2(which comes from the reaction between HgSO3H2AsO3–and H2AsO3–) contributes to the suppression of Hg0re-emission. The results of this study are conducive to providing new insight into Hg0re-emission and mercury control.

This paper investigated the dynamic response of rectangular prestressed membrane subjected to uniform impact load theoretically and experimentally. The dynamic response proceeds in two stages, namely, forced vibration and free vibration. Firstly, the maximal displacement for forced vibration is obtained by means of the principle of minimum potential energy based on the theoretical model proposed. Then, equations of motion for the transverse free vibration are derived based on thin-plate theory, and simplified by using Galerkin method. Consequently, the analytic solutions of dynamic parameters, such as frequency, displacement, amplitude, velocity, and acceleration, for free vibration are obtained by means of the multiple-scale perturbation method. In order to identify the reliability of theoretical model, the corresponding experimental study is carried out based on the developed experimental system. Furthermore, the effects of pretension force and load on the dynamic response of membrane are discussed, respectively. The present work provides a theoretical model to calculate the dynamic response of prestressed membrane subjected to uniform impact load, and a set of experimental system to study this problem.

Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain (NCP). Irrigation, as the most effective way to increase food production in dry land, may not be readily available in the situation of drought. One of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water stress. The objective of this study was to explore effects of irrigation and sulphur (S) application on water consumption, dry matter accumulation (DMA), and grain yield of winter wheat in NCP. Three irrigation regimes including no irrigation (rainfed, I0) during the whole growth period, once irrigation only at jointing stage (90 mm, I1), and twice respective irrigation at jointing and anthesis stages (90 mm plus 90 mm, I2), and two levels of S application including 0 (S0) and 60 kg ha−1(S60) were designed in the field experiment in NCP. Results showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5-23.7% and nitrogen partial factor productivity (NPFP) by 21.2-45.0% in two wheat seasons, but markedly decreased crop water use efficiency (YWUE). Furthermore, S supply 60 kg ha−1significantly increased mean grain yield, YWUE, IWUE and NPFP by 5.6, 6.1, 23.2, and 5.6% (across two wheat seasons), respectively. However, we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of soil. Thus, water supply is still the most important factor to restrict the growth of wheat in the present case of NCP, supplying 60 kg ha−1S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.

The variations of strain and permeability of coal were systematically studied through the physical simulation of N2and water injection. The effects of fluid adsorption capacity and initial permeability on strain, permeability and the dominant effect of pore pressure were discussed. The adsorption strain and strain rate of coal during water injection are significantly higher than those during N2injection. An edge of free adsorption exists in the early phase of N2and water injection, which is related to fluid saturation. Within this boundary, the strain rate and pore pressure are independent. Moreover, the injection time of initial stage accounts for about 20% of the total injection time, but the strain accounts for 70% of the total strain. For water injection, this boundary is about half of water saturation of coal. Besides, the influence of pore pressure on permeability is complex, which is controlled by adsorption capacity and initial permeability of coal. When the initial permeability is large enough, the effect of adsorption strain on permeability is relatively weak, and the promoting effect of pore pressure on fluid migration is dominant. Therefore, the permeability increases with increasing pore pressure. When the initial permeability is relatively low, the pore pressure may have a dominant role in promoting fluid migration for the fluid with weak adsorption capacity. However, for the fluid with strong adsorption capacity, the adsorption strain caused by pore pressure may play a leading role, and the permeability reduces first and then ascends with increasing pore pressure.

Aerosol optical effects can trigger complex changes in solar shortwave radiation (SW) in the atmosphere, resulting in significant impacts on the photochemistry and vertical structure of ozone. This paper provides observational evidence of aerosol absorbing and scattering effects on modifying the SW and ozone profiles in the low troposphere. Using field vertical measurements and observation‐based model simulations, we demonstrated that absorbing aerosols decreased SW, resulting in substantial inhibition of ozone production throughout the boundary layer (BL). A similar inhibition effect occurred within the lower BL under sufficient scattering aerosols. However, the scattering augmentation effect played an additional role in enhancing the photolysis rate and promoting ozone generation in the upper BL. Hence, the observational evidence as well as our model simulations disentangled the radiative effects of different types of aerosols on the vertical structures of ozone. Atmospheric aerosols can modify incident solar radiation by scattering and absorption, resulting in significant impacts on the photolysis rate and photochemical products in the lower troposphere. Such influences could be physically understood, but can only be observed with a detailed vertical measurement system. In this study, through vertical observational data analysis and observational constrained numerical simulations, we found that absorbing aerosols can weaken the shortwave radiation (SW) and photolysis rate in the entire layer, resulting in less ozone formation. In contrast, scattering aerosols enhance the SW and photolysis rate above the aerosol layer and promote ozone formation. Overall, the radiative effects of aerosols lead to an ozone decrease in the low layer and an increase above the boundary layer. Observational evidence of aerosols modifying ozone profiles through their direct radiative effectsAn observation‐based model disentangles the radiative effects of aerosols of different typesAerosol scattering augmentation effect promotes ozone formation in the upper boundary layer Observational evidence of aerosols modifying ozone profiles through their direct radiative effects An observation‐based model disentangles the radiative effects of aerosols of different types Aerosol scattering augmentation effect promotes ozone formation in the upper boundary layer

Nonlinear finite element model of a transmission tower-line system was set up and galloping of iced bundle conductors in the system was numerically simulated by means of ANSYS software. Based on galloping trajectories, vibration frequency, galloping order, conductor tension; unbalanced tension characteristics of iced conductors, it was shown that values of the conductor amplitudes by the tower-line system model are increased by 20% compared to the conductor model. The values of the strain tower unbalanced tensions by the tower-line system model are decreased by 20% and the values of the suspension tower unbalanced tensions by the tower-line system model are decreased by 62.5% compared to the conductor model conductor-insulator mode1. The galloping order is different for different span, due to the impact of the order of galloping. The amplitude of the vertical galloping is increasing while the increasing span, but it is not linear increase.

Study on effective disposal and utilization of sewage sludge has recently been the target of growing interest in China. However, potential risks are associated with the use of sludge due to its contamination with toxic organics, heavy metals and pathogenic microorganisms. In this study, a screening assessment was conducted on sewage sludge samples collected from 17 different sewage treatment plants in Beijing, based on a batch of in vitro bioassays, including a set of recombinant gene yeast assays for endocrine disruption, and an ethoxy resorufin-O-deethylase (EROD) assay using H4IIE cells for aryl hydrocarbon receptor (Ah-R) agonistic activities. Our results suggested that moderate levels of estrogen receptor agonistic activities (0.9 ng E2·g−1to 6.8 ng E2·g−1, dw), but relative higher androgen receptor antagonistic activities (nd to 45%), progestin receptor antagonistic activities (nd to 80%) and Ah-R agonistic activities (1390 to 6740 pg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)·g−1, dw) were found in sewage sludge samples. However, there were no significant correlations between the toxic effects of sewage sludge and the sewage treatment processes. In addition, the 17β-estradiol (E2) equivalent quantity (EEQ) level of the sewage sludge was increased after the composting treatment, whereas the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent quantity (TEQ) level of sewage sludge composted was much lower than that of sewage sludge.

Nanocomposite membranes with enhanced performance were investigated for forward osmosis (FO) by incorporation of nanoporous materials. The incorporation of zeolite into both polysulfone (PSf) substrates and polyamide (PA) rejection layer of thin film composite (TFC) membrane (PSf-TFC) could effectively improve FO membrane performance. In the case of zeolite loading into PA layer, the resulted PSf based thin film nanocomposite (PSf-TFN) membrane showed improved but limited water permeability of the rejection layer, corresponding to ~1.76 times water flux higher than PSf-TFC membrane. Significantly, the polysulfone nanocomposite (PSfN) based TFC membrane (PSfN-TFC), which formed by embedding zeolite nanoparticles in PSf substrates, not only enhanced water permeability of the polyamide rejection layer but also reduced internal concentration polarization (ICP) effect, and thus improved FO membrane performance significantly, which corresponding to ~2.50 times water flux higher than PSf-TFC membrane.

The models of the multi-bundled conductors are constructed by finite element method in this paper. The numerical results are given by using the 4th order Runge-Kutta method considering aerodynamic parameter of sub-conductor. The simulation results are obtained on galloping of quad bundle conductors with the different span. Thus some effective numerical results of quad twin bundle conductor can provide a useful reference for anti-galloping design.

In this paper, 3-DOF finite element model for galloping has been built on the basis of form-finding analysis. Fitting formula about aerodynamic parameters has been obtained by wind tunnel test. With the combination of finite element model and aerodynamic parameter, a simulation model of single bundle on 3-span was built. And the response of ice-coating transmission line was calculated with different span, initial attack angle, wind speed, suspension insulator length and initial tension. With the comparison of the calculated results, span, initial attack angle, wind speed and initial tension have direct effect on galloping amplitude, order of the galloping, load on suspension insulator and tension on the midpoint of span. On the contrary, suspension insulator length doesnt have obvious effect on galloping.

To guarantee the security of composite insulators as tension strings applied to ultra-high voltage engineering, it is necessary to study the mechanical properties of composite insulator regarding break impact. The test system was designed and the implementation plan was developed. Test was done to two insulator strings broken and the dynamic impact factor under different broken conditions at different tension was obtained accordingly, which provides reference and evidence for further study on mechanical properties of composite insulator and development of applicable design specifications.

Dichlorocarbene is added to the sidewalls of single‐walled carbon nanotubes (SWNTs) with diameters ranging from 1.2 to 2.2 nm. Small diameter SWNTs are found to react much more easily than large diameter SWNTs. Upon functionalization, the conductance could be largely preserved for almost all SWNTs, while an effective bandgap increase for functionalized metallic SWNTs (m‐SWNTs) and a bandgap reduction for functionalized semiconducting SWNTs (s‐SWNTs) are generally observed. The results suggest that [2 + 1] cycloaddition is an excellent choice of processing, resulting in SWNTs over a large diameter range with electronic properties that are almost unaffected. Furthermore, possible separation of SWNTs according to their diameters could be achieved due to the apparent diameter‐dependent reactivity.

Based on the summarization of domestic and foreign experience, the computational method of spacer configuration was developed in order to depress sub-span oscillation principally. The requirements of the reverse recovery characteristics were considered. The computer-aided calculation procedures were programmed. The finite element analysis model of sub-span oscillation for cable-spacer system was established. The inherence modal and amplitude for sub-span oscillation of bundled transmission lines were calculated by using numerical simulation method. The dynamic configurations were analyzed by using the parameters of the cable and spacer obtained from vibration testing.

An analysis process for break impact loadings to tower, conductors and unfaulted insulators is proposed when one of the composite multi- insulators tension string comes to rupture. A finite element method is used to simulate the break impact process in order to consider the whole structural model of transmission lines and geometric nonlinearity. And a two-step calculation process, form-finding analysis and break impact analysis, is performed. The calculation results are verified by testing data. And an impact influence coefficient is defined to characterize the influence of maximum impact loading to tower, unfaulted insulators, conductors and fittings. A typical example with the structure of three-composite-insulators string and two/three suspension points is presented. The impact loading characteristics are obtained with different fracture locations. The obtained results are beneficial to design composite multi-insulators tension string structure.

Several key problems in the process of auricle bracket prototyping have been discussed, new research ideas and detailed solutions have been brought forward. Points’ data is acquired through setting rational scan processing parameters and overlapping the data of multiple scans, after analyzing the optimal object functions and strategy, genetic algorithm is used to optimize the prototyping direction, and further separate layers, arrange parts layout and manufacture the prototype. The method can collect more integrated auricle points’ data and optimize in real time. The result shows a perfect optimization has been achieved, after further planning, a satisfactory auricle bracket can be manufactured.

Copper sulfide (CuS) has received increasing attention as a promising material in gaseous elemental mercury (Hg0) capture, yet how to enhance its activity at elevated temperature remains a great challenge for practical application. Herein, simultaneous improvement in the activity and thermal stability of CuS toward Hg0capture was successfully achieved for the first time by controlling the crystal growth. CuS with a moderate crystallinity degree of 68.8% showed a disordered structure yet high thermal stability up to 180 °C. Such disordered CuS can maintain its Hg0capture activity stable during longtime test at a wide temperature range from 60 to 180 °C and displayed strong resistance to SO2(6%) and H2O (8%). The significant improvement can be attributed to the synergistic effect of a moderately crystalline nature and a unique sulfur-rich interface. Moderate crystallinity guarantees the thermal stability of CuS and the presence of abundant defects, in which copper vacancy enhances significantly the Hg0capture activity. The sulfur-rich interface enables CuS to provide plentiful highly active Sx2–sites for Hg0adsorption. The interrelation between structure, reactivity, and thermal stability clarified in this work broadens the understanding toward Hg0oxidation and adsorption over CuS and provides new insights into the rational design and engineering of advanced environmental materials.

KG-augmented models usually endow existing models with external knowledge graphs, which achieve promising performance in various knowledge-intensive tasks, such as commonsense reasoning. Existing methods mainly first exploited heuristic ways for retrieving the relevant knowledge subgraphs according to the input, and then utilized some effective encoders, such as GNNs, to encode the symbolic knowledge into the neural reasoning networks. However, whether the whole retrieved knowledge subgraphs are really relevant or useful for the reasoning process was seldom considered. Actually, according to our observations and analysis, most retrieved knowledge is noisy and useless to the reasoning models, which would hurt the final performance. To remedy this, this paper proposes information bottleneck based knowledge selection (IBKS), which is able to select useful knowledge from the retrieved knowledge subgraph. Expectedly, the selected knowledge could better improve the commonsense reasoning ability of the model. Moreover, IBKS is model-agnostic and could be plugged into any existing KG-augmented model. Extensive experimental results show that IBKS could effectively improve commonsense reasoning performance. [ABSTRACT FROM AUTHOR]