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In this article, a nonlinear static analysis model of a bridge pile foundation is established using numerical simulation, and the correctness of the model is verified via experiments. Then, the damage characteristics and mechanical behaviors of bridge pile foundations in cold regions under lateral loads are investigated based on the validated analysis model. The results showed that the impact of soil freeze–thaw cycles on the lateral performance of the pile–soil system is more pronounced in seasonally frozen regions compared with permafrost regions. Specifically, as the number of soil freeze–thaw cycles increases, there is a tendency for the lateral load capacity of the pile–soil system to decrease initially and then stabilize. It is worth noting that soil freeze–thaw cycles significantly influence both the stiffness and deformation capacity of the pile–soil system, with these parameters exhibiting a decreasing trend followed by stabilization as the number of freeze–thaw cycles increases. However, it has little effect on the shear force and bending moment of the pile foundation. [ABSTRACT FROM AUTHOR]

Fabrication of effective photocatalysts for efficient reactions under mild conditions and light irradiation is significantly important but challenging. Herein, considering both photoresponsive tetra-methoxynaphthyl tetraphenylethylene (NA-TPE) and bi(methyl)viologen-based bipyridine (MV-DPY) molecules as key organic modules, a supramolecular organic framework (SOF) MVDPY-NATPE-CB[8] was assembled in the presence of cucurbit[8]uril (CB[8]) via encapsulation-enhanced donor–acceptor interaction for photocatalytic reactions. Catalytic studies revealed that the assembled MVDPY-NATPE-CB[8] framework can trigger the generation of reactive oxygen species (ROS), including singlet oxygen (1O2) and superoxide anion radicals (O2˙−), for the photocatalytic aerobic oxidation of N-phenyltetrahydroisoquinoline and hydroazobenzene. Moreover, after being coordinated with nickel ions, nickel metallized MVDPY-NATPE-CB[8] (Ni-MVDPY-NATPE-CB[8]) demonstrates a remarkable efficiency in the photocatalysis of the C–S cross-coupling reaction in an aqueous environment. This study demonstrates that rationally assembled photoresponsive SOF materials can be an effective platform for photocatalysis. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are a type of carbon‐based luminescent material with a zero‐dimensional structure and a size of less than 10 nm, which are composed of sp2/sp3 hybrid carbon nuclei and surface functional groups. Because CDs has strong photoluminescence and good light absorption in the ultraviolet and near visible regions, it is an excellent candidate for photocatalytic applications. However, the use of nonmetallic doped CDs as photosensitizers for direct photocatalytic organic reactions has been limited to several scattered reports. Herein, we present nitrogen‐doped carbon dots (N‐CDs) that has a capability for not only produce reactive oxygen species (ROS), including superoxide anion radical (O2⋅−) and singlet oxygen (1O2), but also provide an unprecedented high activity of dehalogenative oxyalkylation of styrene with a yield of 93 %. This work develops a novel opportunity to utilize cost‐effective and easily accessible CDs for the advancement of photocatalysis. [ABSTRACT FROM AUTHOR]

The regulation of type I and type II photosensitizers during the generation of reactive oxygen species (ROS) is a challenging issue in photooxidation reactions. In this study, a novel pyrene-based two-dimensional supramolecular organic framework (SOF) was constructed in water using the host–guest interactions between the methylated vinylpyridine arms of the pyrene derivative (Pmvp) and cucurbit[8]uril (CB[8]), in which the four methylated vinylpyridine arms can be encapsulated by the cavity of CB[8] to form a stable framework structure with periodic pore structure and homogeneous solubility. More importantly, the construction of the SOF can realize the regulation of singlet oxygen (1O2) and superoxide anion radical (O2˙−) generation capacity in ROS production. Specifically, the 1O2 generation capacity decreases, while the O2˙− generation capacity increases, and the SOF exhibits high photocatalytic conversion efficiency in the photocatalysis of the aerobic oxidation of thioanisoles and the oxidative hydroxylation of arylboronic acids in water, with yields up to 87% and 99%, respectively. This study presents an approach based on the concept of SOFs for the effective management of ROS in photooxidation reactions. [ABSTRACT FROM AUTHOR]