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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.

As for cellulose‐based aerogels, a feature of inadequate mechanics and easy‐flammability seriously restricts their practical applications. To address this issue, herein a lightweight, mechanical elastic and flame‐retardant phosphorylated lignin‐based cellulose nanofiber (PLCNF‐B) aerogel with the aid of boric acid was successfully obtained by freeze‐drying method. Due to the uniform and tough network structure benefitting by strong hydrogen bond between phosphorylated fibers and boric acid, the resultant aerogel showed excellent mechanical performance, that is, high compressive strength of 8.9 kPa (strain: 50%) and outstanding cyclic reliability (remain 90% after 10 cycles). Meanwhile, PLCNF‐B aerogel possesses highly improved flame‐retardant property, that is, a high LOI value (up to 46%), significantly reduced peak heat release rate (11.2 W/g) and total heat release rate (0.47 kJ/g). Based on structural observation and analysis, the flame‐retardant behavior should be attributed to the formation of PxOy/amorphous boron oxide protective layer, which is derived from the phosphorus containing group of PLCNF and boric acid. The splendid overall performance of aerogel material offers a potential material tactic for design and development of advanced bio‐based aerogels for practical applications. [ABSTRACT FROM AUTHOR]

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]

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. [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.

Preparing bio‐based epoxy resins with high performance is crucial to sustainable development. However, seeking renewable and flame‐retardant epoxy resins with high mechanical properties are still challenging. Here, we reported a facile way to transform lignin derivatives to intrinsic flame‐retardant epoxy resins with satisfactory mechanical properties. Two guaiacol‐based novolac epoxy resins (i.e., GTEP/DDM and GPEP/DDM) were prepared as alternatives for petroleum‐based DGEBA/DDM. The cured GTEP/DDM product showed a high Tg of 209.5°C, a high tensile modulus of 3.13 GPa, and a high LOI of 28.6% with UL‐94 V‐1 rating, which outperformed DGEBA/DDM system. Specially, GPEP/DDM resin possessed more superior mechanical properties (e.g., tensile strength of 73.9 MPa, and tensile modulus of 5.85 GPa) owing to additional interactions (i.e., π–π interactions and hydrogen bonds), and outstanding anti‐flammability (e.g., LOI of 31.2% with UL‐94 V‐0 rating) due to the endow of phosphorus‐containing groups. The mechanical reinforcement and flame‐retardant mechanisms were clarified based on structural evolution and performance variation. This work provides an efficient synthesis route to achieve a high‐performance thermoset, which is a promising alternative for substituting conventional bisphenol‐A epoxy resin for use as fireproof materials. [ABSTRACT FROM AUTHOR]

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.

We propose GNN-Surrogate, a graph neural network-based surrogate model to explore the parameter space of ocean climate simulations. Parameter space exploration is important for domain scientists to understand the influence of input parameters (e.g., wind stress) on the simulation output (e.g., temperature). The exploration requires scientists to exhaust the complicated parameter space by running a batch of computationally expensive simulations. Our approach improves the efficiency of parameter space exploration with a surrogate model that predicts the simulation outputs accurately and efficiently. Specifically, GNN-Surrogate predicts the output field with given simulation parameters so scientists can explore the simulation parameter space with visualizations from user-specified visual mappings. Moreover, our graph-based techniques are designed for unstructured meshes, making the exploration of simulation outputs on irregular grids efficient. For efficient training, we generate hierarchical graphs and use adaptive resolutions. We give quantitative and qualitative evaluations on the MPAS-Ocean simulation to demonstrate the effectiveness and efficiency of GNN-Surrogate. Source code is publicly available at https://github.com/trainsn/GNN-Surrogate. [ABSTRACT FROM AUTHOR]

The title compound, C10H8I3NO4, crystallizes with two molecules in the asymmetric unit. The I atoms and the benzene ring plane in the two molecules are approximately coplanar, the I atoms deviating by −0.1631 (1), 0.0704 (1) and −0.0507 (1) Å from the mean plane of the benzene ring in one molecule and by 0.1500 (1), −0.0034 (1) and −0.1213 (1) Å in the other. The planes of the ester groups are almost orthogonal to those of the benzene rings in both molecules, forming dihedral angles of 83.5 (3), 76.4 (3), 97.3 (1) and 75.7 (1)°. The mean planes of the benzene rings in two molecules are inclined at 69.8 (3)° with respect to each other. In the crystal, intermolecular I...O interactions link the molecules into infinite chains. In addition, N—H...O and non-classical C—H...O hydrogen bonds are observed.

The carbonyl chloride group in the title compound, C7H3ClN2O5, is disordered over two orientations with occupancies of 0.505 (5) and 0.495 (5). The molecule is approximately planar, the dihedral angle between the carbonyl chloride plane and benzene ring being 9.6 (4)° in the major disorder component and 7.1 (4)° in the minor component. The nitro group at the 5-position is twisted, forming a dihedral angle of 6.7 (4)°. The crystal packing is stabilized by C—H...O hydrogen bonds.

In the title compound, C10H9NO6, the carboxy, ethoxycarbonyl and nitro groups form dihedral angles of 3.8 (1), 4.5 (1) and 164.8 (1)°, respectively, with the mean plane of the benzene ring. In the crystal structure, molecules lying about inversion centers are linked through O—H...O hydrogen bonds. C—H...O interactions are also present.

In the title compound, C8H13N2O2+·Cl−·H2O, the methyl C atom of the ethyl group is slightly out of the imidazole plane, with an N—C(ring)—C—C torsion angle of −15.1 (2)°. In the crystal structure, there are strong intermolecular hydrogen-bonding interactions between the solvent water molecule, the free chloride anion and the organic cation, resulting in a two-dimensional supramolecular network in the ab plane.

In the structure of the title compound, C11H12N2O6, the molecules are stacked along the b axis without any π–π interactions. The stacked columns are linked together by non-classical intermolecular C—H...O interactions,. In the molecule, the nitro groups make dihedral angles of 9.4 (5) and 10.3 (5)° with the benzene ring.

In the title compound, C12H15NO3, the ethoxybenzyl ring plane forms a dihedral angle of 60.3 (4)° with the mean plane of the oxazolidine ring. The molecules are linked through N—H...O hydrogen bonds into a chain running in the b direction.

In the title compound, C11H15NO3, the mean planes of the carboxamide and isopropyl groups are inclined at 109.9 (1) and 128.7 (2)°, respectively, to the mean plane of the phenoxy group. In the crystal structure, molecules are stacked along the b axis, without any π–π interactions. The stacked columns are linked together by intermolecular N—H...O hydrogen bonds, with an N...O distance of 2.842 (2) Å.

The structure of the title compound, C9H7NO6, is essentially planar [maximum deviation 0.284 (2)Å] except for the methyl H atoms. The crystal structure is stabilized by asymmetric O—H...O hydrogen bonds linking the hydrogen carboxylates into pairs around the inversion centres. There is also π–π stacking of the benzene rings [centroid–centroid distance 3.6912 (12) Å].

In the title compound, C11H14N2O5, the nitro group is approximately coplanar with the benzene ring, making a dihedral angle of 4.26 (17)°. The dihedral angle between the methylcarbamate group and the benzene ring is 72.47 (6)°. There is a strong intermolecular N—H...O hydrogen bond between the N and O atoms from adjacent methylcarbamate groups, forming a one-dimensional network along the a axis.

In the molecule of the title compound, C10H9NO6, the two ester groups and the nitro group are inclined at 9.2 (2), 123.3 (6) and 135.2 (5)°, respectively to the mean plane of the benzene ring. In the crystal structure, molecules are stacked along the a axis, without any π–π interactions. The stacked columns are linked together by non-classical intermolecular interactions of the type C—H...O