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Organic bipolar electrodes can undergo both n‐type and p‐type reactions for energy storage due to numerous active sites, which can usually deliver a high theoretical specific capacity. Herein, a new bipolar polymer cathode material PQPZ is designed and synthesized. The electron‐donating phenazine group undergoes a two‐electron redox reaction which can store anions, the electron‐withdrawing phenanthraquinone can store sodium‐ions through a two‐electron redox reaction. Notably, as a bipolar cathode material for sodium‐ion batteries, PQPZ exhibits a reversible specific capacity of up to 270 mAh g−1 in the voltage range of 1.0–4.0 V (vs. Na+/Na) and achieves a high energy density of 696 Wh kg−1 in a half‐cell. A capacity retention rate of 90% is obtained after 300 cycles at a current density of 0.5C. More excitingly, even after being cycled for 10000 cycles at 10C, the PQPZ electrode shows an average decay rate as low as 0.0036% per cycle, manifesting a very stable cycling performance. In addition, PQPZ also shows excellent performances when tested at −10 °C, making it promising in practical applications. Considering the bipolar character of PQPZ, symmetric batteries are also successfully constructed, fulfilling the “ready‐to‐charge” property without a pre‐activation process. The results reveal the potential application of PQPZ in practical use. [ABSTRACT FROM AUTHOR]

Metasurface reveals distinguished application prospects profiting from its excellent manipulating capacity for electromagnetic (EM) wave using ultrathin thickness and the simple design method. Easy to conformal metasurface with high performance and integrated EM functions is highly in demand in many EM devices. Herein, an arched dual‐wavelength cloaking–illusion‐integrated metasurface consisting of two‐layer meta‐atoms is proposed successfully. A composite‐fused deposition molding packaging strategy of additive manufacturing is explored to fabricate the multilayer structures for metal meta‐atoms and dielectric substrates simultaneously. Simulation and measurement results show that the arched metasurface possesses polarization‐insensitive cloaking and illusion functions in 4.3–4.8 and 14.8–16.3 GHz, respectively. The effective incidence angle range covers from −45° to 45°. The excellent EM camouflage performance proves the effectiveness of our design and fabricating strategy, which paths a way for multifunctional metasurface‐based devices. [ABSTRACT FROM AUTHOR]

Long‐term exposure to respirable silica particles causes pulmonary inflammation and fibrosis primarily promoted by cytokines released from alveolar macrophages, yet the underlying mechanism is still unclear. From the perspective of nuclear factor kappa B (NF‐κB), we studied the mechanism of IL‐1β biosynthesis and release. Utilizing BAY 11‐7082, an NF‐κB specific inhibitor, we showed the alteration of macrophage viability and examined the expression of both IL‐1β and NF‐κB in vitro. We found that silica nanoparticles (SiNPs) were internalized by macrophages and caused damage to cell integrity. The immunofluorescence assay showed that SiNPs exposure enhanced the expression of IL‐1β and NF‐κB, which could be effectively suppressed by BAY 11‐7082. Besides, we built silica exposure mouse model by intratracheally instilling 5 mg of SiNPs and checked the effect of silica exposure on pulmonary pathological changes. Consistently, we found an upregulation of IL‐1β and NF‐κB after SiNPs exposure, along with the aggravated inflammatory cell infiltration, thickened alveolar wall, and enhanced expression of collagens. In conclusion, SiNPs exposure causes pulmonary inflammation and fibrosis that is regulated by NK‐κB through upregulating IL‐1β in alveolar macrophages. [ABSTRACT FROM AUTHOR]

The curved surfaces conformality has become the coming barrier to the implementation of the metasurface carpet cloaks. A curved conformal strategy that can balance the electromagnetic performances and the manufacturing challenges of metasurface simultaneously is highly in demand, but yet underexplored. Herein, a novel thermal programming 3D‐printing method for curved conformal metasurface is proposed. Owing to the glass‐rubber transition characteristics of thermoplastic polymers, the advantages of rigid substrate and flexible substrate are fully utilized to achieve the conformality of metasurface, which ingeniously reduces the manufacturing complexity and ensures the electromagnetic performances. As a proof, an arched metasurface carpet cloak composed of the easy‐bending unit cells is designed and fabricated by the composite fused deposition molding of polylactic acid and Sn‐Bi materials with the thermal programming process. Experiments prove that the maximum reduced total radar cross section of the conformal cloak reaches about −9.4 dB while the 3 dB reduction bandwidth is ≈26.6%. The excellent cloaking performance of the metasurface sample demonstrates the effectiveness of this curved conformal method. This work provides a viable implementation strategy for complex curved metasurface and will substantially promote the applications of the conformal invisibility cloaks. [ABSTRACT FROM AUTHOR]