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With the development of aerospace technology, protective materials for hot-end components have reached higher requirements. In this paper, a （ZrxY（1-x/4）Ta（1-x/4）Ti（1-x/4）Er（1-x/4））O（x=0.2，0.544，0.672，0.796和0.92）quintuple element ceramic system composite is studied based on the solid-phase reaction method and molecular dynamics simulation. By experimental means, ZrO2 （99.99%）, Y2O3 （99.99%）, Ta2O5 （99.99%）, Er2O3 （99.99%） and TiO2 （99%） powder was used as raw material to prepare （ZrxY（1-x/4）Ta（1-x/4）Ti（1-x/4）Er（1-x/4））O composite by the solid-phase reaction method. The thermal conductivity of （ZrxY（1-x/4）Ta（1-x/4）Ti（1-x/4）Er（1-x/4））O ceramic material was investigated computationally using the LAMMPS program. The study result shows that a consistent trend in the variation of the thermal conductivity is obtained by experiments and simulations at the interval of 200-900 °C. The thermal conductivity reaches a minimum value at x = 0.796, which proves the feasibility of molecular dynamics simulation of the thermal conductivity of multi-ceramic materials. Meanwhile, the effect of porosity on thermal conductivity was investigated, and it is found that there was a competitive relationship between the elemental ratios and the effect of porosity on thermal conductivity. When the porosity is larger than 6.67%, the effect of the porosity is the main influencing factor. when the porosity is smaller than 6.67%, the elemental ratios are the dominant factors in the thermal conductivity.

To achieve the optimal alginate-based oral formulation for delivery of hydrophobic drugs, on the basis of previous research, we further optimized the synthesis process parameters of alginate-g-oleylamine derivatives (Ugi-FOlT) and explored the effects of different degrees of substitution (DSs) on the molecular self-assembly properties of Ugi-FOlT, as well as the in vitro cytotoxicity and drug release behavior of Ugi-FOlT. The resultant Ugi-FOlT exhibited good amphiphilic properties with the critical micelle concentration (CMC) ranging from 0.043 mg/mL to 0.091 mg/mL, which decreased with the increase in the DS of Ugi-FOlT. Furthermore, Ugi-FOlT was able to self-assemble into spherical micellar aggregates in aqueous solution, whose sizes and zeta potentials with various DSs measured by dynamic light scattering (DLS) were in the range of 653 ± 25~710 ± 40 nm and −58.2 ± 1.92~−48.9 ± 2.86 mV, respectively. In addition, RAW 264.7 macrophages were used for MTT assay to evaluate the in vitro cytotoxicity of Ugi-FOlT in the range of 100~500 μg/mL, and the results indicated good cytocompatibility for Ugi-FOlT. Ugi-FOlT micellar aggregates with favorable stability also showed a certain sustained and pH-responsive release behavior for the hydrophobic drug ibuprofen (IBU). Meanwhile, it is feasible to control the drug release rate by regulating the DS of Ugi-FOlT. The influence of different DSs on the properties of Ugi-FOlT is helpful to fully understand the relationship between the micromolecular structure of Ugi-FOlT and its macroscopic properties. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In this study, a novel approach is proposed to achieve the uniformly dispersed Ru nanoparticles with N coordination loaded on three‐dimensionally ordered macro/mesoporous carbon (3DOMMC) through simultaneous pyrolysis of Ru3+ and cyanamide on 3DOMMC. In an alkaline medium, the synthesized catalysts exhibit exceptional hydrogen evolution reaction (HER) performance. Specifically, Ru‐N/3DOMMC demonstrates a significantly low overpotential of 13.8 mV to achieve a current density of 10 mA·cm–2, and it exhibits a mass activity 17.5 times higher than that of commercial Pt/C. The outstanding performance could be attributed to the ultrahigh Ru dispersion and more efficient contact between active sites and reactant, which derived from the large specific surface area and interconnective three‐dimensionally macro/mesopores of 3DOMMC. [ABSTRACT FROM AUTHOR]

To investigate the influence of the Hutuo River (North China) ecological water replenishment project on the hydrogeochemical processes of groundwater, 64 groundwater samples collected at different time intervals after four replenishment events, and four samples from the Middle Route of the South-to-North Water Diversion Project water, were analyzed for water chemistry. Hydrogeochemical methods such as the Piper diagram, chloride-alkalinity index, and ion correlation were employed to analyze the characteristics of groundwater chemical evolution through replenishment. The results demonstrated that the hydrochemical types of groundwater in the study area underwent significant changes during continuous replenishment in the Hutuo River region. During the initial replenishment period (October 2019), the dominant hydrochemical type of groundwater in the study area was Mg-Na-HCO3-SO4, whereas the dominant type in the Middle Route of the South-to-North Water Diversion Project water was Ca-Na-SO4-HCO3. As the replenishment continued, the hydrochemical types of groundwater in the study area evolved into Ca-Na-Mg-HCO3-SO4, Na-Ca-Mg-HCO3-SO4, and Ca-Na-Mg-SO4-HCO3. The groundwater experienced a dissolution of calcite, gypsum, nitratine, carbonate rocks, and gypsum, accompanied by dilution effects, resulting in reduced ion exchange as replenishment progressed. The input of the high quality Middle Route of South-to-North Water Diversion Project water effectively promoted groundwater quality improvement, leading to an overall decrease or stabilization of components other than Ca2+ in the groundwater. Water quality was assessed using the entropy water quality index, with indicators including Na+, SO42−, Cl−, pH, total dissolved solids, NO3−-N, NO2−-N, F−, Al, As, and Zn. The evaluation results showed that, except for one medium-quality water sample, the water quality of the other samples was suitable for drinking and domestic purposes during the early replenishment period. The Middle Route of the South-to-North Water Diversion Project exhibited excellent quality (Rank 1), and as replenishment progressed, all water samples demonstrated good quality by October 2020, with a gradual improvement. [ABSTRACT FROM AUTHOR]

The electrification of transportation in the past few decades has sparked the retirement of lithium‐ion batteries (LIBs) which hinders sustainability derived from environmental impact and valuable elements loss through improper disposal. The challenges of recycling spent LIB are contamination, complicated processes, massive chemical/energy consumption, and secondary pollution. Here, a material and energy dual circulations method is proposed for a closed‐loop and sustainably recycling the components in spent LIBs. In the material circulation, the cathode, anode, and the accessories, like castings, aluminum‐plastic films, and binders, are recycled by electrochemical dual‐electrode recycling technology to regenerate LIBs and fabricate a triboelectric nanogenerator (TENG). In energy circulation, the fabricated TENG converts ambient wind energy into electricity to continuously power the material circulation by forming a self‐powered system. This system shows high element selectivity (Li, 99.7%; Ni, 96.1%; Co, 97.3%; and Mn, 97.2%), self‐powering, a simplified treating procedure, and high profit, which makes it feasible for commercial application. [ABSTRACT FROM AUTHOR]