Actuators have wide applications in intelligent robots, deformable textiles, and wearable devices, wherein the fiber‐based coiled linear actuators are particularly advantageous due to their good flexibility, high stress, and strain. However, their performances have been limited by the employed materials, whose microstructures are not easily designed and controlled. This article proposes a new approach of engineered composite yarns for the actuators. It leads to novel solutions to overcome these difficulties by offering wide design options in material properties and device structures. Here, an engineering design of programmable and thermally‐hardening helical composite yarn actuators (HCYAs) with a wide range of operating temperature is exemplified. Polyimide (PI) and polydimethylsiloxane (PDMS) are selected to fabricate HCYAs, achieving tensile actuation of 20.7% under 1.2 MPa from −50 °C to 160 °C and competitive specific work (158.9 J kg^‐1, four times of natural muscle). With constant tensile deformation, PI/PDMS HCYA nearly tripled the stress from 20 °C to 100 °C. Moreover, it is surprisingly observed an unusual thermal‐hardening phenomenon that the tensile stiffness of the PI/PDMS HCYAs increases with the rise of temperature. Equipped by electrothermally powered PI/Cu/PDMS HCYAs, robotic hands and pressure‐tunable compressive bandage are demonstrated for their potential applications in robots and wearable devices.

Extended from our previous finding that poly (3-hydroxybutyrate) (PHB) oligomer is an effective antimicrobial agent against gram-positive bacteria, gram-negative bacteria, fungi and multi-drug resistant bacteria, this work investigates the effect of polyethylene glycol (PEG) on the antimicrobial effect of PHB oligomer. To investigate and explain this promoting phenomenon, three hypothetic mechanisms were proposed, that is, generation of new antimicrobial components, degradation of PHB macromolecules and dissolution/dispersion of PHB oligomer by PEG. With a series of systematic experiments and characterizations of high-performance liquid chromatography–mass spectrometry (HPLC-MS), it was deducted that PEG promotes the antimicrobial effect of PHB oligomer synergistically through dissolution/dispersion, owing to its amphipathy, which improves the hydrophilicity of PHB oligomer.

Front Cover: PHB oligomer with a few degrees of polymerization is discovered to possess effective antibacterial and antifungal properties. Produced by ring‐opening polymerization of β‐butyrolactone or extraction from fermented PHB, the oligomer imparts antimicrobial ability to non‐antibacterial fabrics with washing‐resistance. The synthesized oligomer offers effective sterilization and promotes the wound healing of infected nude mice. The oligomer is reactive to drug‐resistant bacteria. This is reported by Linlin Ma, Ziheng Zhang, Jun Li, Xingxing Yang, Bin Fei, Polly H. M. Leung, Xiaoming Tao in the article 1800432.

To produce well loaded mesoporous aluminum-based adsorbents for defluoridation of zinc sulfate solution, novel Al/Ce hybrid gel (AC) and Al/Nd hybrid gel (AN) were synthesized with high water-soluble pseudo-boehmite as the main raw material. The properties, optimal defluoridation conditions, synthesis principle and adsorption mechanism were studied via related characterizations, experiments, and models. The results obtained revealed that the main bodies of AN and AC are AlO(OH). Ce(CH₃COO)₃ and Nd(CH₃COO)₃ are embedded in the frameworks, forming large amounts of ink-bottle type mesopores. The experimental data of both AC and AN fitted well to the pseudo-second-order kinetic and Langmuir isotherm models. Maximum adsorption capacities of AC and AN for fluoride ions were 26.57 mg g⁻¹ and 29.18 mg g⁻¹, respectively. The larger adsorption capacity indicated that the aluminum-based adsorbent modified by Nd element for the first time has a promising application prospect in defluoridation. The adsorbents showed high fluoride ion adsorption speeds with the removal rates reaching 50.15% (AC) and 33.41% (AN) within 2 min at 50 °C, 3 g l⁻¹. The mechanism analysis revealed that the electrostatic interaction of protonated hydroxyl with fluoride ions and coordination between rare earth ions and fluoride ions are involved in the adsorption. Ce(CH₃COO)₃ and Nd(CH₃COO)₃ embedded in the main body stabilize the structure of the adsorbents, enhance the defluoridation speeds, and provide adsorption sites for fluoride ions.

Thermal management relying on passive radiative cooling materials can result in remarkable energy savings and greenhouse gas emissions reductions compared with traditional air conditioner-based cooling. However, few of these materials are degradable; thus, their disposal may generate a new environmental problem. At the same time, the COVID-19 pandemic and other infectious diseases have raised requirements for hygienic and antimicrobial performance. In this work, we use a facile solvent evaporation method to prepare a novel hierarchically porous polylactic acid oligomer (PLAO) coating that exhibits a radiative cooling effect, broad-spectrum antimicrobial properties, and degradability (with a degradation rate of 99.5% after 28 days). The radiative cooling effect is attributed to the hexagonal microsphere geometry and nanotexture of the polylactic acid oligomer (PLAO) crystals, which enhance reflectivity in the solar spectrum through a multiple scattering effect and exhibit high emissivity in the mid-infrared atmospheric window. The hierarchically porous PLAO coating material achieves an apparent temperature reduction of 6.8 °C under solar-spectrum irradiation (AM 1.5). The material also shows broad-spectrum antimicrobial and antiviral properties against coronaviruses (including the COVID-19 virus), with a reduction rate of 99.99% after 20 min; Gram-positive and Gram-negative bacteria, with a reduction rate of 99.99% after 1 h; fungi, with a reduction rate of 98.4% after 1 h; and multidrug-resistant bacteria, against which it produces a 0.22 cm inhibition ring after 12 h.

The old VLCC was taken as the study object, the PHAST software was used to simulate the oil film range of collision in the old VLCC, and predict the damage areas of the fire and explosion accidents caused by the collision. The simulation results had certain reference significance for the risk analysis in the old VLCC for offshore oil storage enterprise.