Hefei Institutes of Physical Science

The normal zone propagation velocity (NZPV) in high-temperature superconductors (HTS) is two to three orders of magnitude lower than that in low-temperature superconductors (LTS). This slow quench propagation poses a critical challenge for quench detection in HTS applications. Fiber Bragg Grating (FBG) sensors have demonstrated potential as cryogenic sensors for quench detection in HTS applications. But determining an appropriate threshold value for the central wavelength shift (Δλ) in quench detection remains a question to be addressed. In this paper, both single superconducting tapes and stacked tapes, which serve as the fundamental building blocks of HTS cables, are investigated. The time delay of the FBG sensor is demonstrated to be shorter than that of voltage taps when a hotspot occurs at the grating location. The Δλ corresponding to quench temperature—the threshold examined in this study—decreases as the distance from the hotspot increases. The FBG can effectively respond to a quench event more quickly than voltage, when the distance from the hot spot is less than 10 mm.

Multi-active-site additives with strong reactivity are an effective strategy to continuously improve device efficiency, and also contribute to the long-term stability of perovskite solar cells (PSCs). However, achieving efficient interaction between all active sites and the perovskite remains a critical challenge. Among various structural modifications, methyl substitution, the simplest functional unit in organic chemistry, offers a unique methylation effect that strongly depends on its positional configuration within a molecule, thereby providing a promising approach to modulate additive reactivity. In this study, we designed and investigated two positional methylation isomers, 1-methylhydantoin (1-MH) and 5-methylhydantoin (5-MH), and demonstrate rational positional methylation can significantly enhance the multisite reactivity of additives with perovskite materials. While both isomers contribute to improved device efficiency, they exhibit markedly different effects on device stability. Notably, the incorporation of 5-MH enabled a power conversion efficiency (PCE) of 26.84% (certified at 26.78%), and delivered outstanding operational stability, retaining 92% of its initial PCE after 2000 h under the ISOS-L2 protocol.

ABSTRACT Endothelial cells (ECs) form the dynamic interface between blood and tissue, serving as key regulators of vascular homeostasis, inflammation, and repair. Among the molecular systems governing endothelial behavior, the C‐X‐C motif chemokine receptor (CXCR) family—originally characterized in immunology for its roles in leukocyte trafficking and immune signaling—has recently emerged as a pivotal regulator of vascular biology. Accumulating evidence indicates that CXCRs orchestrate endothelial development, angiogenesis, and injury responses through context‐dependent signaling mechanisms. This review integrates recent advances in endothelial CXCR research, highlighting their molecular functions and translational relevance. We first describe the developmental and homeostatic subgroup in which CXCR4 and its atypical partner CXCR7/ACKR3 coordinate vascular morphogenesis and regeneration. In parallel, we contrast the proangiogenic ELR + receptors (CXCR1 and CXCR2) with the angiostatic ELR − receptor CXCR3 and discuss the emerging roles of CXCR5 and CXCR6 in linking chronic inflammation and adaptive immunity to vascular dysfunction. Collectively, these findings position the CXCR family as an integrated network that fine‐tunes endothelial phenotype and vascular fate, revealing new opportunities for precision therapeutic intervention.