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Reconfiguration of architected structures has great significance for achieving new topologies and functions of engineering materials. Existing reconfigurable strategies have been reported, including approaches based on heat, mechanical instability, swelling, origami/kirigami designs, and electromagnetic actuation. However, these approaches mainly involve physical interactions between the host materials and the relevant stimuli. Herein, a novel, easy‐manipulated, and controllable reconfiguration strategy for polymer architectures is proposed by using a chemical reaction of host material within a hydrogel reactive microenvironment. 3D printed polycaprolactone (PCL) lattices transformed in an aqueous polyacrylamide (PAAm) hydrogel precursor solution, in which ultraviolet (UV) light triggered heterogeneous grafting polymerization between PCL and AAm. In situ microscopy shows that PCL beams go through volumetric expansion and cooperative buckling, resulting in transformation of PCL lattices into sinusoidal patterns. The transformation process can be tuned easily and patterned through the adjustment of the PCL beam diameter, unit cell width, and UV light on–off state. Controlling domain formation is achieved by using UV masks. This framework enables the design, fabrication, and programming of architected materials and inspires the development of novel 4D printing approaches. [ABSTRACT FROM AUTHOR]

Exploring the possible catalytic effect of black phosphorus quantum dots (BPQDs) with specific exposed planes on chemiluminescence (CL) to improve CL intensity and achieve excellent analytical performance is one of the latest research hotspots. Herein, uniform BPQDs with highly exposed (113) facets and an average size of 2.2 nm were fabricated via a facile ultrasonic exfoliation strategy. The enhanced CL intensity in the BPQDs–luminol–K3Fe-(CN)6 system is attributed to the catalytic effect of BPQDs. The catalytic mechanism of BPQDs involved in luminol–K3Fe-(CN)6 CL is revealed by theoretical calculations, which show an adsorption Gibbs free energy for oxygen of −0.86 eV, accompanied by the separation of electron–hole pairs (e––h+). In other words, after being irradiated by the CL generated from luminol and K3Fe-(CN)6, the BPQDs effectively catalyze the decomposition of dissolved oxygen to produce superoxide radical anions, which further react with luminol to increase CL emission. The noticeable suppression of the CL signal in the presence of dopamine acquired under mild conditions makes it attractive for biosensor applications, deepening the understanding of BPQDs as efficient catalysts and promoting the potential development of BPQD-based materials in the fields of photonics, biomedicine, and electronics. [ABSTRACT FROM AUTHOR]

Fibre‐based wearables for embroidery, chemosensing, and biofluid's unidirectional draining with good flexibility, tunability, and designability drive technological advance. However, synthetic polymer fibres are non‐degradable, threatening the environment and human health. Herein, we have developed versatile microfibre‐based wearables by combining many advantages in one platform of biodegradable polylactic acid (PLA) and melt electrowriting strategy. Diverse potential applications of PLA wearables are achieved by flexibly designing their printing files, components and structures. Three‐dimensional printing files are generated from two‐dimensional images to fabricate 'embroidery‐like' patterns. PLA/aggregation‐induced emission fluorogens (AIE) chemosensors exhibit colorimetric and fluorescent colour changes upon exposure to amine vapours. Janus PLA‐cotton textiles with a hydrophobic/hydrophilic structure could facilitate unidirectional draining of sweats which is favourable for the management of temperature and humidity on the surface of skin. The proposed platform can not only broaden the design possibilities in 3D/4D printing but also offer wide potential applications for functional wearables. [ABSTRACT FROM AUTHOR]

Bismuth sulfide (Bi2S3) with micro/nanostructures as an important semiconductor material has attracted considerable attention due to its high ionic conductance, high photoelectric conversion efficiency, and large absorption coefficient, which is widely applied in the areas of photocatalysis, energy conversion, sensors, biomedicine, and pollutant disposal. Up to now, various strategies are reported for the morphology‐controlled synthesis of micro‐nanoscale Bi2S3 and Bi2S3‐based materials via manipulating the thermodynamics and kinetics in the chemical fabricating process. However, the Bi2S3 with designed shapes still remains to be developed to well adapt these diverse usages. To conclude, the designed preparation strategies, advanced applications, current challenges, and future expectations of Bi2S3 are discussed to provide some potential suggestions for further promotion of Bi2S3 functional materials. [ABSTRACT FROM AUTHOR]

At an extremely high Mach number, the regenerative cooling of traditional kerosene cannot meet the requirement of the heat sink caused by aerodynamic heating and internal combustion in a scramjet propulsion system. As a supplement of traditional regenerative cooling, supercritical CO2 is regarded as an effective coolant in severe heating environments due to its excellent properties of heat and mass transportation. In this paper, the heat transfer and flow structure characteristics of regenerative cooling in a rectangular channel using supercritical CO2 are analyzed numerically using a validated model. The effect of heat flux magnitude, nonuniform heat flux, acceleration and buoyancy and flow pattern are considered to reveal the regenerative cooling mechanism of supercritical CO2 in the engine condition of a scramjet. The results indicate that the heat transfer deterioration phenomenon becomes obvious in the cooling channel loaded with relatively high heat flux. Compared with the cooling channels loaded with increased heat flux distribution, the maximum temperature increased for the channel loaded with decreased heat flux distributions. When larger acceleration is applied, a relatively lower wall temperature distribution and higher heat transfer coefficients are obtained. The wall temperature distribution becomes more uniform and the high-temperature region is weakened when the coolants in adjacent channels are arranged as a reversed flow pattern. Overall, the paper provides some references for the utilization of supercritical CO2 in regenerative cooling at an extremely high Mach number in a scramjet. [ABSTRACT FROM AUTHOR]

Biomechanics, which provides a good insight into the mechanical properties of various parts and tissues of living organisms, is an important part of medical science and provides the fundamental theoretical knowledge of mechanics for medical science. Biomechanics helps to provide a precise model of complex tissues, improves the quantitative measurement of mechanical properties, offers some assistance to engineering applications, and aids in the clinical management of the patient. Meanwhile, advanced experimental and computational biomechanics has become an important component for understanding the physiological and pathological conditions of human biological tissues. Analysis of the role of collagen in airway mechanics quantifies macro- and micro-scale approaches to airway mechanics and pathological changes associated with collagen deposition in airway disease in the quest to treat airway pathology and address airway defects [[9]]. [Extracted from the article]

Hydrogen peroxide (H2O2) sensors with high sensitivity and stable detecting ability have been particularly in demand in the charming medical health and environmental monitoring. In this work, spherical ZnFe2O4/g-C3N4 (ZFO/g-C3N4) nano/microcomposites with different contents of g-C3N4 were controllably synthesized through a solvothermal calcination strategy, and the morphologies of their target materials were systematically characterized via scanning electron microscopy, energy dispersive spectroscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Subsequently, the as-prepared spherical ZFO/g-C3N4 composites are designed as an outstanding electrochemical sensor for H2O2, and its sensitivity was evaluated using cyclic voltammetry and chronoamperometry techniques. The ZFO/g-C3N4 microspheres exhibited a synergistic catalytic effect with a broad linear detection range between 5 and 200 μM and a detection limit of 1 μM (S/N = 3). The enhanced electrochemical performances of uniform ZFO/g-C3N4 composites with a three-dimensional net structure proved that the combination of a two-dimensional material (C3N4) and spinel-type metal oxide (ZnFe2O4) produces apparent activity, showing broad application potential in nonenzymatic sensors. [ABSTRACT FROM AUTHOR]