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Due to its high reactivity and oxidative strength, singlet oxygen (1O2) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1O2 is extremely challenging. Herein, we describe a one‐dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3O2 (triplet oxygen) to 1O2. CP1 consists of CdII centers bridged by 9,10‐bis((E)‐2‐(pyridin‐4‐yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1O2, resulting in the generation of CP1−1O2. Using microwave irradiation, CP1−1O2 displays efficient release of 1O2, over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through‐space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1O2, using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors. [ABSTRACT FROM AUTHOR]

Due to its high reactivity and oxidative strength, singlet oxygen (1O2) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1O2 is extremely challenging. Herein, we describe a one‐dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3O2 (triplet oxygen) to 1O2. CP1 consists of CdII centers bridged by 9,10‐bis((E)‐2‐(pyridin‐4‐yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1O2, resulting in the generation of CP1−1O2. Using microwave irradiation, CP1−1O2 displays efficient release of 1O2, over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through‐space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1O2, using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors. [ABSTRACT FROM AUTHOR]

Acute myocardial infarction (AMI) is one of the main causes of death in the world, and the incidence of AMI is increasing in the young population. Drug-coated balloon (DCB) has become an effective concept for the treatment of in-stent restenosis, small vessel disease, bifurcation lesions, high blood risk conditions, and even de novo large vessel disease. To ensure whether DCB can play an alternative role in AMI, we conducted a comprehensive meta‐analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of DCB in the treatment of AMI. Electronic databases were searched for RCTs that compared DCB with stent for AMI. The primary outcome was major adverse cardiac events (MACEs), the secondary outcome was late lumen loss (LLL). RevMan 5.3 software and RStudio software were used for data analysis. Five RCTs involving 528 patients with 6–12 months of follow-up were included. There was no significant difference in the incidence of MACEs between DCB group and stent group (RR, 0.85; 95% CI 0.42 to 1.74; P = 0.66). Lower LLL was shown in DCB group (WMD, − 0.29; 95% CI − 0.46 to − 0.12; P < 0.001). This meta-analysis of RCT showed that DCB might provide a promising way on AMI compared with stents. Rigorous patients' selection and adequate predilation of culprit lesions are necessary to optimize results and prevent bailout stent implantation. PROSPERO registration number: CRD42020214333. [ABSTRACT FROM AUTHOR]

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

To construct hetero-/homo-junction is an effective way to improve the performance of photocatalyst. However, some basic and important issues about the underlying mechanism of this strategy still need to be further confirmed and explained. In the present work, the interfacial properties of α / β -Bi 2 O 3 composite photocatalyst with homo-junction are in-depth investigated by density functional theory calculations. Owing to partially saturated dangling bonds, the electronic structure of interface model exhibits both the features of bulk and surface models. Importantly, the interfacial states are mainly arising from the layer of β -Bi 2 O 3 @Interface. At the interface of α / β -Bi 2 O 3 homo-junction, the energy bands of β -Bi 2 O 3 are relatively down-shifting compared with those of α -Bi 2 O 3 , resulting in form the staggered gaps (type II), which is very favorable for the improvement of photocatalytic performance. Moreover, the built-in electric field of homo-junction points from β -Bi 2 O 3 layer to α -Bi 2 O 3 layer under equilibrium, so the photon-generated electron–hole pairs can be spatially separated by the α / β -Bi 2 O 3 homo-junction. Furthermore, to construct α / β -Bi 2 O 3 homo-junction not only keep the advantageous of visible-light absorption of β -Bi 2 O 3 , but also improve the visible-light absorption of α -Bi 2 O 3 . [ABSTRACT FROM AUTHOR]

We report a unique vinyl coordination polymer (CP), [Zn(4‐Fb)2(tkpvb)]n (1, 4‐HFb=4‐fluorobenzoic acid, tkpvb=1,2,4,5‐tetrakis(4‐pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two‐dimensional CP integrated with a one‐dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1‐PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization‐driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs‐based smart photoactuators in the burgeoning field of microrobotics. [ABSTRACT FROM AUTHOR]

We report a unique vinyl coordination polymer (CP), [Zn(4‐Fb)2(tkpvb)]n (1, 4‐HFb=4‐fluorobenzoic acid, tkpvb=1,2,4,5‐tetrakis(4‐pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two‐dimensional CP integrated with a one‐dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1‐PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization‐driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs‐based smart photoactuators in the burgeoning field of microrobotics. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims to investigate the durability properties of recycled aggregate concrete treated with silane-based water repellent agents, since the high water absorption of recycled aggregate concrete is a major factor jeopardizing its durability. Different dosages of silane-based water repellent agents were either coated on the surface of the concrete (hereafter “surface silane treatment”) or integrally added into the concrete mixture (hereafter “integral silane treatment”). The mechanical and durability properties of the treated concrete were evaluated. It was found that integral silane treatment can improve the durability of recycled aggregate concrete, but may lead to reductions in compressive strength; surface silane treatment is more effective in improving the resistance of recycled aggregate concrete to capillary water absorption, carbonation and chloride penetration than integral silane treatment. [Copyright &y& Elsevier]