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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]

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]

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]

Objectives: Methods: Results: Conclusions: The aims of this research were to characterise the injury patterns associated with nail guns, highlight their potential complications and review treatment options. A retrospective case series was conducted of all patients with a nail gun injury to the upper or lower limb who presented to the Princess Alexandra Hospital from 1 January 2007 to 30 July 2012. Young men in the work environment were at most risk of sustaining a nail gun injury to their non-dominant hand. Out of 87 cases identified, 29% were intra-articular, 16% had evidence of neurovascular injury, 24% involved bone and 37% had evidence of tendon injury. Fifty-eight per cent underwent operative management, 32% were treated solely in the ED and 10% were transferred to a private facility. At the time of operation, 14% of cases had tendon, joint or neurovascular involvement and 20% had retained foreign material. The median length of operation was 17 min and no anaesthetic complications were identified. Four (13%) patients had ongoing pain, paraesthesia or stiffness at the time of follow up. The present study characterises the injury patterns caused by nail guns. Treatment of these injuries should be based on clinical findings; however, the majority of cases should undergo surgical treatment. The required operation is a short and safe treatment modality that might allow a thorough assessment of the injury, removal of embedded material, repair of structural damage and a sterile washout to be performed. [ABSTRACT FROM AUTHOR]

The title compound, C16H24O10·0.11H2O, is a key intermediate in the synthesis of 2-deoxy-2-[18F]fluoro- d-glucose (18F-FDG), which is the most widely used molecular-imaging probe for positron emission tomography (PET). The crystal structure has two independent molecules ( A and B) in the asymmetric unit, with closely comparable geometries. The pyranose ring adopts a 4 C1 conformation [Cremer-Pople puckering parameters: Q = 0.553 (2) Å, θ = 16.2 (2)° and ϕ = 290.4 (8)° for molecule A, and Q = 0.529 (2) Å, θ =15.3 (3)° and ϕ = 268.2 (9)° for molecule B], and the dioxolane ring adopts an envelope conformation. The chiral centre in the dioxolane ring, introduced during the synthesis of the compound, has an R configuration, with the ethoxy group exo to the mannopyranose ring. The asymmetric unit also contains one water molecule with a refined site-occupancy factor of 0.222 (8), which bridges between molecules A and B via O-H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Advanced conductive hydrogels demonstrate substantial potential for wearable devices. Nevertheless, the transformative advance in soft electronics raises harsh requirements on the hydrogel candidates, such as rapid and on‐site fabrication, mechanical flexibility, high sensitivity, and wide use temperature. Here, this problem is overcome by incorporating a dual catalytic system based on lignin‐modified MXene‐Fe3+ into commercial hydrogels. This system 1) can form a composite hydrogel in a time scale of min at ambient condition without the supply of external energy, 2) incorporates multiple enhanced strategies into polymer chains, and 3) constructs well‐organized hybrid conductive network. The fabricated hydrogel displays an improved and balanced overall performance, including high ductility (2139%), moderate electrical conductivity, and strong temperature tolerance (−70–50 °C). Combined with the great merits of above performance, the hydrogel‐based sensor with good sensing (maximum GF: 2.8), stable repeatability (200% for 200 cycles), and wide work window of 0%–947%, thereby disclosing promising application in physiological movements, such as motion recognition and breathing state detection. Sensationally, even in complex or harsh surroundings, the sensors also produce stable and reliable signal output. Together, the strategy provides a new mentality of designing hydrogel materials for booming and advanced wearable electronics. [ABSTRACT FROM AUTHOR]

In the title compound, C10H10N2O6·H2O, the carb-oxy-lic 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 inter-actions link the organic mol-ecules and water mol-ecules of crystallization into a three-dimensional supra-molecular architecture.

The title compound, C(10)H(8)I(3)NO(4), crystallizes with two mol-ecules in the asymmetric unit. The I atoms and the benzene ring plane in the two mol-ecules 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 mol-ecule 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 mol-ecules, 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 mol-ecules are inclined at 69.8 (3)° with respect to each other. In the crystal, inter-molecular I⋯O inter-actions link the mol-ecules 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, C(7)H(3)ClN(2)O(5), is disordered over two orientations with occupancies of 0.505 (5) and 0.495 (5). The mol-ecule 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, C(10)H(9)NO(6), the carb-oxy, ethoxy-carbonyl 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, mol-ecules lying about inversion centers are linked through O-H⋯O hydrogen bonds. C-H⋯O inter-actions are also present.

In the title compound, C(8)H(13)N(2)O(2) (+)·Cl(-)·H(2)O, 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 inter-molecular hydrogen-bonding inter-actions between the solvent water mol-ecule, the free chloride anion and the organic cation, resulting in a two-dimensional supra-molecular network in the ab plane.

In the structure of the title compound, C(11)H(12)N(2)O(6), the mol-ecules are stacked along the b axis without any π-π inter-actions. The stacked columns are linked together by non-classical inter-molecular C-H⋯O inter-actions,. 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, C(12)H(15)NO(3), the ethoxy-benzyl ring plane forms a dihedral angle of 60.3 (4)° with the mean plane of the oxazolidine ring. The mol-ecules are linked through N-H⋯O hydrogen bonds into a chain running in the b direction.

In the title compound, C(11)H(15)NO(3), 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 phen-oxy group. In the crystal structure, mol-ecules are stacked along the b axis, without any π-π inter-actions. The stacked columns are linked together by inter-molecular N-H⋯O hydrogen bonds, with an N⋯O distance of 2.842 (2) Å.

The structure of the title compound, C(9)H(7)NO(6), 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 carboxyl-ates 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, C(11)H(14)N(2)O(5), the nitro group is approximately coplanar with the benzene ring, making a dihedral angle of 4.26 (17)°. The dihedral angle between the methyl-carbamate group and the benzene ring is 72.47 (6)°. There is a strong inter-molecular N-H⋯O hydrogen bond between the N and O atoms from adjacent methyl-carbamate groups, forming a one-dimensional network along the a axis.

In the mol-ecule of the title compound, C(10)H(9)NO(6), 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, mol-ecules are stacked along the a axis, without any π-π inter-actions. The stacked columns are linked together by non-classical intermolecular interactions of the type C-H⋯O.