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Abstract With the continuous development of economy, engineering construction is developing towards deep high-stress area, and the problems of large-deformation engineering are becoming more and more serious. Anchoring grouting is a very effective support reinforcement method. The anchoring grouting materials used in the project are mainly cement paste and cement mortar. The characteristics of the grouting material have a decisive influence on the grouting effect. However, it is difficult for the existing grouting materials to satisfy the requirements of strength and deformation at the same time, and improvement is urgently needed. Polycaprolactone (PCL) is an organic polymer material of good engineering properties, including high ductility, good stability and strong impact resistance. In this paper, PCL was added as an auxiliary additive to cement-based materials innovatively, and the mechanical test and micro-test of PCL-cement-based materials were carried out. The results show that adding PCL can significantly increase the compressive strength of cement paste. By adjusting the content of PCL, the strength and ductility of cement mortar can be effectively improved. When the content of PCL is 15%, ideal high performance cement mortar material can be obtained. Anchor grouting is a very effective reinforcement and support method.

The boundary layer transition process induced by different heights and quantities of the cylindrical roughness elements at Mach 3.0 is investigated experimentally by using the nano-tracer-based planar laser scattering (NPLS) technique. Fine structures of the boundary layers of both streamwise and spanwise induced by the cylindrical roughness elements in the supersonic flow are obtained, and the development of the boundary layer in the roughness element wakes is observed. The boundary layer after reattachment will keep the laminar state within a certain distance, meanwhile hairpin vortexes can be observed clearly during the development of the boundary layer. The fractal theory is used to quantitatively analyze the NPLS images of the boundary layer. This method can achieve the positions of the boundary layer transition in several cases. The research results show that the interaction between multiple roughness elements can inhibit the boundary layer transition and the evolution of hairpin vortexes. However, when the roughness elements on both sides are higher than those in the middle, the interaction between roughness elements has no obvious inhibitory effects on the development of the boundary layer.

The derivatization of pillar[n]arenes is a prerequisite for endowing them with functions, as well as enriching the application of pillar[n]arene materials in advanced material science. Herein, we report the self‐assembly of amphiphilic rim‐differentiated pillar[5]arene (H1). One side of the pillar[5]arene is composed of hydrophilic poly(ethylene oxide) chains, benzene and azobenzene groups connected with ether bonds, and the other side is composed of ethoxy groups. In CHCl3 solvent, the amphiphile H1 self‐assembled into spherical micelles, while in H2O/THF mixed solvent H1 self‐assembled into nanorod‐like assemblies. Interestingly, addition of a guest molecule composed of tetraphenylethene and hexanenitrile groups (G1) to the CHCl3 solution of H1 produces large sheet aggregates via the strong π–π stacking of rod segments. The reversible transformation between the nanosheet assemblies of host–guest complexes and nanoparticles is achieved by addition of the guest molecule 1,4‐butylamine (G2) and pillar[5]arene with ethoxy groups as competitive molecules. Notably, worm‐like and nanorod micelles of H1 were constructed in H2O/THF solution triggered by light irradiation, which assemblies can be used as photosensitive erasable writing materials. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The field of fluorescence sensing, leveraging various supramolecular self-assembled architectures constructed from macrocyclic pillar[n]arenes, has seen significant advancement in recent decades. This review comprehensively discusses, for the first time, the recent innovations in the synthesis and self-assembly of pillar[n]arene-based supramolecular architectures (PSAs) containing metal coordination sites, along with their practical applications and prospects in fluorescence sensing. Integrating hydrophobic and electron-rich cavities of pillar[n]arenes into these supramolecular structures endows the entire system with self-assembly behavior and stimulus responsiveness. Employing the host–guest interaction strategy and complementary coordination forces, PSAs exhibiting both intelligent and controllable properties are successfully constructed. This provides a broad horizon for advancing fluorescence sensors capable of detecting environmental pollutants. This review aims to establish a solid foundation for the future development of fluorescence sensing applications utilizing PSAs. Additionally, current challenges and future perspectives in this field are discussed. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry enables the manipulation of functional components on a molecular scale, facilitating a "bottom-up" approach to govern the sizes and structures of supramolecular materials. Using dynamic non-covalent interactions, supramolecular polymers can create materials with reversible and degradable characteristics and the abilities to self-heal and respond to external stimuli. Pillar[n]arene represents a novel class of macrocyclic hosts, emerging after cyclodextrins, crown ethers, calixarenes, and cucurbiturils. Its significance lies in its distinctive structure, comparing an electron-rich cavity and two finely adjustable rims, which has sparked considerable interest. Furthermore, the straightforward synthesis, uncomplicated functionalization, and remarkable properties of pillar[n]arene based on supramolecular interactions make it an excellent candidate for material construction, particularly in generating interpenetrating supramolecular polymers. Polymers resulting from supramolecular interactions involving pillar[n]arene find potential in various applications, including fluorescence sensors, substance adsorption and separation, catalysis, light-harvesting systems, artificial nanochannels, and drug delivery. In this context, we provide an overview of these recent frontier research fields in the use of pillar[n]arene-based supramolecular polymers, which serves as a source of inspiration for the creation of innovative functional polymer materials derived from pillar[n]arene derivatives. [ABSTRACT FROM AUTHOR]

Despite the fact that effective photosensitizers (PSs) can be achieved through rational molecular design, controlling the hierarchical assemblies of individual PSs with distinct function and morphological nanoscopic architectures remains a challenge. Here, very ordered one-dimensional PS polymers and their hollow tubular structures are presented from aqueous assembly of organic PS-based di- or tri-blocked supramolecules. Di-blocked PSs were interdigitated into 1D fibrils, significantly quenching photooxidation. Meanwhile, tri-blocked PSs were tilted with respect to each other to generate hollow tubules, showing remarkable photo-activities as well as photo-stability, which are particularly suited for green chemistry due to their unusual rapid photo-oxidation. [ABSTRACT FROM AUTHOR]