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The novel hollow-magnetite (HFO)/MXene nanohybrids with coral-like structure were successfully prepared via templating and electrostatic self-assembly techniques for electromagnetic (EM) wave adsorption application. The unique coral-like structure of the prepared HFO/MXene hybrids was characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). When mass ratio of HFO to MXene is 2:1, the maximum effective absorption bandwidth (EAB max) of HFO/MXene hybrids is able to reach 5.36 GHz. Moreover, when mass ratio of HFO to MXene is 1:1, the minimum reflection loss (RL min) even achieves −42.48 dB with a thickness of 3.1 mm. The excellent EM absorption performance of HFO/MXene hybrids is mainly due to the ideal impedance matching and synergistic effect of magnetic loss and dielectric loss caused by unique coral-like structure. This work provides unexplored areas in the design of the spatial structure of MXene for microwave absorption. [Display omitted] • HFO/MXene hybrids with unique coral-like structure was prepared by templating and electrostatic self-assembly method. • Hollow Fe 3 O 4 are distributed in MXene, which provides magnetic losses and improves the impedance matching. • RL min achieves −42.48 dB with a thickness of 3.1 mm, and maximum EAB max is able to reach 5.36 GHz. [ABSTRACT FROM AUTHOR]

Gamma-aminobutyric acid (GABA), a non-protein-producing amino acid synthesized from the excitatory amino acid glutamate via the enzyme glutamic acid decarboxylase, is extensively found in microorganisms, plants and vertebrates, and is abundantly expressed in the spinal cord and brain. It is the major inhibitory neurotransmitter in the mammalian nervous system. GABA plays crucial roles in the regulation of synaptic transmission, the promotion of neuronal development and relaxation, and the prevention of insomnia and depression. As the major inhibitory neurotransmitter, GABA plays pivotal roles in the regulation of pain sensation, which is initiated by the activation of peripheral nociceptors and transmitted to the spinal cord and brain along nerves. GABA exerts these roles by directly acting on three types of receptors: ionotropic GABA A and GABA C receptors and G protein-coupled GABA B receptor. The chloride-permeable ion channel receptors GABA A and GABA C mediate fast neurotransmission, while the metabotropic GABA B receptor mediates slow effect. Different GABA receptors regulate pain sensation via different signaling pathways. Here we highlight recent updates on the involvement of specific GABA receptors and their subtypes in the process of pain sensation. Further understanding of different GABA receptors and signaling pathways in pain sensation will benefit the development of novel analgesics for pain management by targeting specific GABA receptor subtypes and signaling pathways. [Display omitted] • GABA regulates synaptic transmission contributing to pain sensation. • GABA A receptor regulates membrane potential depending on transmembrane chloride gradient. • GABA A receptor-mediated analgesic effects rely on subunits compositions. • GABA B receptor modulates pain transmission. [ABSTRACT FROM AUTHOR]

A task allocation problem for heterogeneous unmanned aerial vehicles (UAVs) in the presence of environment uncertainty is studied in this paper. Generally, the process of finding efficient allocation scheme can be computationally prohibitive. This work presents a Q-learning based fast task allocation (FTA) algorithm through neural network approximation and prioritized experience replay, which effectively offloads the online computation to an offline learning procedure. Specifically, the proposed approach develops a Q network that encodes the allocation rules. The Q network not only considers the effect of environment uncertainty, but also is capable of handling total different tasks. Comparison simulations are provided to show the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The applications of dielectric capacitors are essential for modern pulsed-power and high-power electronic devices. Antiferroelectric ceramics have garnered much attention as promising materials for capacitive energy storage on account of their ultrahigh recoverable energy density (W rec). However, the relatively high energy loss originating from electric field induced antiferroelectric-ferroelectric (AFE-FE) phase transition results in low energy storage efficiency (η). Herein, the La3+ ions incorporated (Pb 0.98 Sr 0.02)(Zr 0.85 Sn 0.15)O 3 antiferroelectric ceramics were explored to obtain stable antiferroelectric phase and trigger a unique multistage AFE-FE(Ⅰ)-FE(Ⅱ) phase transition simultaneously. Consequently, this strategy led to the achievement of an ultrahigh W rec of 13.9 J/cm3 and an enhanced η of 80.4% in the optimal composition. Notably, these ceramics have also demonstrated exceptional thermal reliability of W rec and η in a wide temperature range, outperforming other previously reported PbZrO 3 -based ceramics. These results offer an efficient approach to promote the capacitive energy storage behavior in antiferroelectric ceramics. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TG-FTIR) and on-line FTIR were employed in this study, aiming at investigating the pyrolysis characteristic of Polybenzylic Ether Phenolic resin sand mould (PEP-SET sand) and emission gases generated during casting. The non-isothermal pyrolysis of PEP-SET sand can be subdivided into three stages: emission of inherent moisture (below 215 °C), thermal decomposition at low temperature (215–315 °C) and further cracking process at high temperature (315–432 °C). The main emission gaseous products in pyrolysis processes were H 2 O, CO 2 , NH 3 , CH 4 , C 2 H 6 , NO and a little amount of CO, according to the FTIR spectrum analyses. The amount of N-containing pyrolysis products generated from cracking of the C N bond reflects the collapse extent of the binder. The thermal shock tests at different temperatures were performed. Similar to non-isothermal pyrolysis processes, the main gaseous products were CO 2 , CO, NO, CH 4 and C 2 H 6 under thermal shock conditions, and these gases released follow a fixed sequence: concentrations of CO, CO 2 and NO firstly increased to the peaks and then decreased with the rising of CH 4 and C 2 H 6 . At last the CO 2 concentration increased again. The major emission oxidizing gas which may induce ignition of Mg melt is CO 2 and the environmental hazardous components are NO and NH 3 . [ABSTRACT FROM AUTHOR]

A novel poly(aspartic acid) based PASP-l-PAHy hydrogel possesses the comprehensive merits of injectability, self-biodegradability, shape-adaptability, transparence, biocompatibility, and adhesion is reported. The hydrogel could seamlessly fill and stably adhere to skin incisions, and accelerate wound healing process. [Display omitted] • Designing and developing a novel versatile poly(aspartic acid) hydrogel. • The multiple crosslinks of chemical bonds (amide bond) and physical bonds (ionic bond and hydrogen bond) endows the hydrogel with comprehensive merits. • Desired autolytic biodegradation ensures removal trauma of wound dressing after 10 days. • The poly(aspartic acid) based hydrogel accelerates rat skin full-thickness wound healing. Severely chronic dermal wounds with irregular rupture shapes or even cavities are calling for injectable and self-biodegradable wound dressings for skin lesion with complex contours remain a great challenge. Here, we report an injectable, self-biodegradable poly(aspartic acid)-l-poly(aspartyl hydrazide) (PASP-l-PAHy) hydrogel to address these issues. The starting materials were cheap, and the new strategy for fabrication of self-biodegradable poly(aspartic acid) based hydrogel was facile, efficient, mild and environmentally friendly, which is consistent with the concept of green chemistry. The hydrogel possesses the comprehensive merits of injectability, self-biodegradability, shape-adaptability, transparence, biocompatibility, and adhesion, and shows specific autolytic biodegradation. The hydrogel was generated by in-situ gelation of poly(aspartic acid) (PASP) and poly(aspartyl hydrazide) (PAHy) polymers based on dual chemical (amide bond) and physical (hydrogen bond and ionic bond) crosslinks. The acceleration of wound healing could be observed in a rat skin full-thickness wound model for repairing skin tissue defects via hydrogel injection and autolytic biodegradation, highlighting great potential applications in wound dressing for the irregular dermal lesions without secondary skin damage. The injectable and self-biodegradable hydrogel augments formation of blood vessels and mature granulation tissue, thus enabling faster skin tissue restoration outcomes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Different proportions of MoS 2 /MnO 2 adsorbents were synthesized. • Mm-30 adsorbents show great removal efficiency for mercury. • Mm-30 have a higher specific surface area than pure MoS 2. • The adsorption of Hg on Mm-30 follows the M−K mechanism. • Mm-30 adsorbent has good resistance to SO 2 under the condition of 400 ppm S+ N 2. In this work, MoS 2 /MnO 2 synthesized by hydrothermal methods was employed to remove Hg0 in flue gas. Benefited from the growth of MnO 2 on the surface of MoS 2 , the specific surface area of the Mm adsorbent has increased. Compared with pure MoS 2 , specific surface area of Mm-30 has increased by 26.0287 m2/g. The MoS 2 modified with 30 w.t. % MnO 2 revealed higher mercury removal performance at 120 °C, which reached 93%. The oxidation of mercury over Mm-30 is proposed to follow Mars-van Krevelen mechanism, whereby the lattice oxygen in the adsorbent is consumed. In presence of NO, HCl, O 2 and SO 2 , the effect of different concentrations on mercury oxidation is observed. Mm-30 adsorbent reveals stable mercury removal performance in the presence of NO and HCl, while it also exhibited good sulfur resistance under the condition of 400 ppm SO 2 + N 2. This phenomenon indicates that the adsorbent can be applied in power plants with medium concentrations of SO 2 , which facilitated the application of Mm-30 as a potential mercury removal adsorbent for power plants. [ABSTRACT FROM AUTHOR]

• A stochastic distribution system planning with energy storage degradation is solved. • Energy arbitrage and regulation services are co-optimized for siting and sizing. • A Gaussian mixture model is adopted to generate stochastic scenarios. • A modified progressive hedging algorithm which outperforms Gurobi is introduced. With the trend of energy storage participating in ancillary service markets, it is still computationally burdensome to incorporate the rapidly changing real-time signals in the long-run distribution system planning. In this paper, a two-stage stochastic programming is proposed for the distribution system with energy storage, where the storage degradation and ancillary service revenue for frequency regulation are both considered. For this purpose, the problem is formulated as a mixed-integer linear programming optimizing the overall planning cost, including investment and maintenance cost, power transaction cost and revenue from regulation services. A degradation penalty is added in the objective to avoid excessive charge/discharge when providing regulation services, thus further benefiting the economy of the distribution system. The model also considers uncertainties of load demand and electricity prices. A Gaussian mixture model is adopted to characterize these uncertainties and a set of representative scenarios are sampled. To accelerate the optimization, a modified progressive hedging with parallel computing is proposed. It is demonstrated through a 33-bus distribution system that the proposed algorithm has a speed approximately 15 times as fast as the state-of-art commercial software Gurobi when solving the model in 100 scenarios. For this case study, considering degradation penalty has been shown to extend energy storage lifespan by one year. [ABSTRACT FROM AUTHOR]

• HCN emissions in a typical FCC unit were much higher than expected. • O 2 content in regenerator affects the emission of nitrogen-containing gas greatly. • Low O 2 content could decrease HCN emission under partial combustion. Stringent environmental regulations have made HCN emission from fluid catalytic cracking (FCC) unit attracted more attention. HCN is always considered as a volatile intermediate, which is transformed into NO x after oxidation. However, the on-site monitoring data from a typical FCC unit in this work showed that HCN emissions were much higher than expected. The spent FCC catalysts were analyzed by different methods to identify HCN precursors, and found that pyridinic nitrogen (N-6), pyrrolic nitrogen (N-5), and quaternary nitrogen (N-Q) are the main precursors of HCN. In the regeneration process, most of pyridinic nitrogen was transformed into NH 3 and HCN, while the rest were partially oxidized to N-5, and the degree of oxidization conversion is related to regeneration temperature and oxygen concentration. A series of experiments were conducted on a fixed-bed regenerator to evaluate the effects of different regeneration conditions on the nitrogen-containing gas emission. Experiment results demonstrated that low oxygen concentration is beneficial to the reduction of HCN emission during the partial combustion regeneration stage. Under complete combustion condition, with excess oxygen content, the contents of NO, HCN and NO 2 are much higher than these under partial combustion conditions, indicating that the oxygen content affects the emission of nitrogen-containing gas significantly. [ABSTRACT FROM AUTHOR]

Violet phosphorus (VP) has emerged as the most stable and biocompatible allotrope of phosphorus. Our study first reported the synergistic anti-cancer effects by combination treatment of violet phosphorene nanosheets (VPNS) and cold atmospheric plasma (CAP) in vitro and in vivo. VPNS-1 exhibited remarkable efficacy in inhibiting tumor growth by suppressing arachidonic acid metabolism, while CAP induced cancer cell apoptosis through the increase of reactive oxygen species (ROS). Moreover, the key role played by AKT and anti-apoptotic proteins of the Bcl-2 family (Bcl-2, Bcl-xL, and Mcl-1) in the induction of apoptosis in VPNS-CAP treatment was demonstrated. Our combination therapy just like "tai chi", controlling cancer cell growth and death with low or no side effect. [Display omitted] • VPNS-1 and CAP have synergistic anti-cancer effects by in vitro and in vivo. • VPNS-1 inhibit tumor growth by suppressing arachidonic acid metabolism in vivo. • AKT, Bcl-2, Bcl-xL and Mcl-1inhibition by co-treatment to induce cell apoptosis. • VPNS-1 and CAP treatment show low or no side effects in vivo. Violet phosphorene nanosheets (VPNS), another type of two-dimensional nonmetal nanostructure, is a promising nanomaterial for biomedical applications. Cold atmospheric plasma (CAP) is an emerging anti-cancer strategy. Here, for the first time, a synergistic combination of VPNS and CAP exhibited remarkable efficacy in cancer treatment. Our findings revealed that VPNS and CAP effectively suppress cancer cell viability by inhibiting cell proliferation and inducing cell apoptosis in vitro. Moreover, we demonstrated the synergistic anti-cancer effect of VPNS and CAP in vivo , with low or no side effects. By metabolism analysis in vivo , we first reported that VPNS-1 inhibited tumor growth by down-regulating Delta-12-Prostaglandin J2, 8,9-DiHETrE, and Hepoxilin B, thereby suppressing arachidonic acid metabolism. Additionally, the down-regulation of AKT and anti-apoptotic proteins (Bcl-2, Bcl-xL and Mcl-1) of Bcl-2 family contributed to the inhibition of cell growth and the initiation of cell apoptosis. Our results unveiled a novel and promising anti-cancer approach involving the combined treatment of VPNS and CAP. [ABSTRACT FROM AUTHOR]

Highlights • Multi-physical CFD model is developed by considering Seebeck effect. • Thermoelectric currents and thermoelectric-magnetic effects during MSLBW are calculated. • The influence of TECs on weld pool dynamics is characterized. • Simulation data is validated by experimentally determined seam morphologies. Abstract Thermoelectric currents (TECs) caused by Seebeck effect were usually neglected in welding simulation. This paper characterizes the TECs and thermoelectric-magnetic phenomena during the magnetically supported laser beam welding (MSLBW) of thick aluminum (Al) alloy. The simulation is based on a computational fluid dynamic (CFD) model developed in three dimensions. The model considers multi-physical mechanisms including thermal transfer, solid–liquid (S/L) transition, molten metal convection, magnetohydrodynamics (MHD) and Seebeck effect. The computed TEC distribution in laser welding pool highly depends on welding time and temperature gradient. The large current densities occur near the weld pool edge and the vectors are opposite at both side of S/L interface. The maximum TEC density obtained in the stabilized weld pool is 2.14 × 106 A/m2, leading to a self-induced magnetic field of 2.27 × 10−3 T and a Lorentz force of 2.62 × 103 N/m3. The influences of TECs on weld pool dynamics are quite limited in LBW but notable in MSLBW. The inversion of MF direction leads to different Lorentz force distributions, weld pool dimensions and seam profiles. The simulation data agrees well with the experimental results. [ABSTRACT FROM AUTHOR]

• A comprehensive predictive method of electricity consumption and load for Chinese rural residences is proposed. • The hourly electricity usage behavior of different seasons are analyzed. • The predictive method is verified at individual and regional scale. • The influence laws of usage behavior on electricity consumption and load for a certain case is explored. Electricity consumption and load prediction, and the influence laws of usage behavior are essential for smart grid and policy guidance. This paper presents an electricity consumption and load prediction method based on a stochastic model considering the randomness and seasonality in the usage behavior of appliances, with the aim of exploring the influence laws of the usage behavior. According to the proposed method, a model was developed and verified by taking certain regional rural residences as examples, and the influence of model inputs on electricity consumption and load were explored. The results showed that the modeled total electricity consumption of individual and regional rural residences were consistent with the actual values. The prediction accuracy of the model could be improved by more than 30% compared with the deterministic model results. Furthermore, the model could reasonably capture the electricity load profiles on a daily as well a seasonal basis. Our research provides a comprehensive framework to predict the electricity consumption and load for Chinese rural residences from sampling and data acquisition to model development, and to preliminarily explore the power demand characteristics and significant influencing factors, which may provide valuable data for power grid design and photovoltaic power generation systems. [ABSTRACT FROM AUTHOR]

Strontium carbonate (SrC) bioceramics are proposed as potential biomaterials to efficaciously repair the bone defects. However, the development of SrC bioceramics is restricted by their intrinsic low mechanical strength. In this study, SrC-based composite bioceramics (SrC-SrP) were fabricated by incorporating strontium-containing phosphate glass (SrP). The results indicated that aside from the main crystalline phase SrC, new compounds were generated in the SrC-SrP bioceramics. Incorporating 10 wt% SrP promoted densification, thus dramatically improving compressive strength of SrC-SrP bioceramics. The SrC-SrP bioceramics facilitated apatite precipitation on their surface, and sustainedly released strontium, phosphorus and sodium ions. Compared with the well-known β-tricalcium phosphate bioceramics, the SrC-SrP bioceramics with certain amounts of SrP enhanced proliferation, alkaline phosphatase activity and osteogenesis-related gene expressions of mouse bone mesenchymal stem cells. The SrC-SrP bioceramics with appropriate constituent can serve as novel bone regenerative biomaterials. [Display omitted] • Strontium carbonate-based composite bioceramics (SrC-SrP) were fabricated. • Strontium-containing phosphate glass (SrP) was incorporated into bioceramics. • Incorporating 10 wt% SrP dramatically improved compressive strength of SrC-SrP. • SrC-SrP facilitated apatite precipitation on the surface. • SrC-SrP enhanced proliferation and osteogenic differentiation of cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient chiral bioreactor (LAAO/HRP@ZIF-8) was first fabricated by in situ method. • Enhanced catalytic efficiency, stability and reusability of immobilized LAAO/HRP were achieved. • The chiral signal of amino acids (AAs) can be easily converted to fluorescence signal. • The bioreactor facilitates the discrimination and quantitation of multiple chiral AAs. Effective discrimination and quantitation of Amino acid (AA) enantiomers is enormously pivotal in diverse fields ranging from pharmaceutics to biological systems. We herein proposed a one-step strategy to construct a novel cascade bioreactor for chiral sensing of multiple AA enantiomers by coupling L-amino acid oxidase (LAAO) and Horseradish peroxidase (HRP) into zeolitic imidazolate framework-8 (ZIF-8) (LAAO/HRP@ZIF-8). LAAO specifically catalyzes L-AAs to α-keto acid, ammonium and H 2 O 2 , and then the yielded H 2 O 2 oxidizes o-phenylenediamine (OPD) to strong yellow fluorescence signal of 2,3-diaminophenazine (DAP) by wrapped HRP. ZIF-8 not only guaranteed free enzymes stability owing to the steric confinement effect of the framework, but also reinforced multi-enzyme cascade catalytic activity due to a preconcentration effect of the analyte inside the cavities. In view of this, the fabricated chiral sensor allowed highly sensitive enantioselectivity discrimination a range of chiral AA enantiomers, especially tryptophan (Trp), valine (Val), methionine (Met), phenylalanine (Phe), isoleucine (Ile), leucine (Leu) and alanine (Ala). According to the linear correlation between the content of L-AAs and fluorescence intensity, this sensor achieved the quantitative determination of Enantiomeric excess (ee) value with high accuracy, and the results were well matched with those obtained by High performance liquid chromatography (HPLC). Additionally, the prominent stability and satisfactory reusability of this sensor were favorably elucidated by using Trp as the model molecule. Our work provides an unprecedented protocol for enantioselective fluorescence discrimination and quantitative determination of ee value for AA enantiomers, and immensely advances the promising application field of multi-enzyme@metal-organic framework biocomposites. [ABSTRACT FROM AUTHOR]

• A simple high-temperature calcination method was used to produce metallic molybdenum disulfide (1 T-Li x MoS 2). • The phase change increases the active site. • ML-100 adsorbent has good mercury removal efficiency and cycle stability. • Density functional theory(DFT) was used to verify the increase in surface activity after 2H-MoS 2 phase changed to 1 T-MoS 2. In this work, a simple high-temperature calcination method was used to produce metallic molybdenum disulfide (1 T-Li x MoS 2). Experiments and simulations show that 1 T-MoS 2 has stronger surface activity and enhances the adsorption capacity of Hg0, thereby effectively removing elemental mercury (Hg0) in coal-fired flue gas. Sample ML-100 could maintain a mercury removal efficiency of approximately 92% after 6-cycle experiments, and approximately 97% efficiency could be maintained throughout a long-term experiment. The proposed method converts the 2H phase to the 1 T phase by doping commercial MoS 2 with lithium ions, thereby improving the removal efficiency of elemental mercury in the flue gas. [ABSTRACT FROM AUTHOR]