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Abstract MXene‐based thermal camouflage materials have gained increasing attention due to their low emissivity, however, the poor anti‐oxidation restricts their potential applications under complex environments. Various modification methods and strategies, e.g., the addition of antioxidant molecules and fillers have been developed to overcome this, but the realization of long‐term, reliable thermal camouflage using MXene network (coating) with excellent comprehensive performance remains a great challenge. Here, a MXene‐based hybrid network comodified with hyaluronic acid (HA) and hyperbranched polysiloxane (HSi) molecules is designed and fabricated. Notably, the presence of appreciated HA molecules restricts the oxidation of MXene sheets without altering infrared stealth performance, superior to other water‐soluble polymers; while the HSi molecules can act as efficient cross‐linking agents to generate strong interactions between MXene sheets and HA molecules. The optimized MXene/HA/HSi composites exhibit excellent mechanical flexibility (folded into crane structure), good water/solvent resistance, and long‐term stable thermal camouflage capability (with low infrared emissivity of ≈0.29). The long‐term thermal camouflage reliability (≈8 months) under various outdoor weathers and the scalable coating capability of the MXene‐coated textile enable them to disguise the IR signal of various targets in complex environments, indicating the great promise of achieved material for thermal camouflage, IR stealth, and counter surveillance.

The recycling of cathode materials for spent NCM has always been a major concern for the energy industry. However, among the current processing methods, the general leaching efficiency of Li is between 85% and 93%, with much room for improvement. The recovery of Ni, Co and Mn requires a high cost of secondary purification. In this study, to recycle the NCM cathode material, a route of sulphated reduction roasting – selective Li water leaching – efficiency acid leaching of Ni, Co, Mn – extraction separation – crystallisation was adopted. The results showed that after roasting (a temperature of 800 °C, a reaction time of 90 min, a carbon content of 26%, and a sulphuric acid addition of nH2SO4:nLi = 0.85), Li water leaching efficiency was 98.6%, followed by acid leaching of Ni, Co and Mn at around 99%. Mn, Co were extracted with Di-(2-ethylhexyl) phosphoric acid and 2-Ethylhexyl phosphonic acid mono-2-ethylhexyl ester respectively to obtain Ni, Co, Mn solutions, which eventually were crystallized for manganese sulphate, cobalt sulphate, lithium carbonate and nickel sulphate products, with high purity of 99.40%, 98.95%, 99.10%, and 99.95%. The results of this study improved the leaching efficiency of Li and were closely linked to the actual industrial preparation of Ni, Co and Mn sulphates, providing a feasible and promising basis for spent NCM cathode materials industrial recovery. [ABSTRACT FROM AUTHOR]

Hyperbranched polysiloxane (HSi) molecules with tunable molecular structure were synthesized and served as a novel crosslinker for fabricating polyacrylamide/chitosan (PCH) hydrogels. Various characterizations demonstrated that HSi molecules with tunable bi-functional vinyl and epoxy groups were successful prepared and utilized to optimize the network architecture and interactions of polymer chains. Benefiting from the structure of bi-functional crosslinker, PCH hydrogels demonstrated remarkably improved mechanical properties, superior to that of conventional crosslinker or HSi with single vinyl or epoxy group. A tensile strength of 302 kPa, elongation at break of 2263%, and toughness of 3.85 MJ·m–3 can be achieved by optimizing the molecular structure and content of HSi with bi-functional group (e.g. ratio of vinyl/epoxy = 0.68). Additionally, such hydrogels showed outstanding antifatigue ability to withstand cyclic compressive tests. Based on the structure observation and analysis, the improved mechanical properties are likely derived from the combination of homogeneous and strong polymer network and improved interactions of polymer chains (e.g. covalent and hydrogen bonds). Approaches in this study may inspire the design and development of novel crosslinker for fabricating mechanically robust hydrogels. Keywords: Hyperbranched polysiloxane, Tunable molecular structure, Hydrogel, Mechanical properties, Chitosan

Background. Torus or buckle distal radius fractures are common injuries in the pediatric population. By definition, they are stable and can be treated conservatively with a wrist splint or soft crepe bandage. Objective. The objective of this study was to evaluate the utility of serial radiographs in the clinical outcome of children with stable distal radius buckle fractures. Materials and Methods. A one-month retrospective analysis was undertaken at two major hospitals in Queensland—Logan and Redlands Hospital. Statistical analysis was performed to identify any relationships between serial radiographs and certain demographic parameters including fracture characteristics, age, sex, and limb side. Results. Of the 136 patients, 50% had more than one radiograph series taken. A total of 576 single radiographs and 251 radiograph series were taken. All fractures healed without complications and did not require active intervention. There was a statistically significant relationship (p=0.0015) between fracture angulation and multiple radiographs series. A cost analysis revealed $55,890 per year could be saved by not performing serial radiographs. Conclusion. Serial radiographs did not appear to change the excellent clinical outcome for children with distal radius buckle fractures. There is a potential to reduce costs and prevent unnecessary ionizing radiation exposure to children.

The recovery of iron phosphate involves the addition of oxidizer to oxidize Fe2+ in the spent LiFePO4 (LFP) material to Fe3+ and the agent commonly used is hydrogen peroxide (H2O2). Nevertheless, H2O2 has disadvantages of high price, easy decomposition and low utilization efficiency. In this manuscript, a facile method is proposed for efficient synergistic oxidation of Fe2+ in spent LFP leachate with a mixture of oxygen and ozone. Specifically, we found by thermodynamic computations that the dominant oxidation groups of ozone during oxidation varied with acidity. The oxidation would produce a large number of iron-phosphate complex groups (Fe3H6(PO4)43+, FeH8(PO4)4− and Fe2HPO44+) in the phosphorus-sulfur mixed acid system, leading to a paradoxical pH drop. The optimized conditions for H2O2 oxidation were explored. It was determined experimentally that oxidation by gas mixture and O2 belonged to the firstorder and second-order reactions with activation energies of 28.68 kJ/mol and 34.61 kJ/mol, respectively, which were both controlled by a mixture of chemical reaction and diffusion. The optimized oxidation method was finally determined by evaluating the cost and oxidation rate of the oxidizers. The results in this study offer a promising method for new low-cost and efficient Fe2+ oxidation for industrial production. [ABSTRACT FROM AUTHOR]

In the title compound, C10H10N2O6·H2O, the carboxylic acid group and the nitro group are essentially coplanar with the benzene ring [maximum deviation = 0.0264 (9) Å], while the amide group is oriented at a dihedral angle of 9.22 (5)° with respect to the benzene ring. In the crystal, classical O—H...O and N—H...O hydrogen bonds and weak C—H...O interactions link the organic molecules and water molecules of crystallization into a three-dimensional supramolecular architecture.