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Halogen bonds (XB) induce successive amorphous to single-crystalline transformations in iodobismuthate perovskites, and improve the water-resistance. DFT computations show the Bi–I bond nature determines the semiconductivity of the materials.

Anisotropic thermally conductive composites are very critical for precise thermal management of electronic devices. In this work, in order to prepare a composite with significant anisotropic thermal conductivity, polyamide 12/styrene–acrylic copolymer–boron nitride (PA12/SA–BN) composites with macro and micro double anisotropic structures were fabricated successfully using 3D printing and micro-shear methods. The morphologies and thermally conductive properties of composites were systematically characterized via SEM, XRD, and the laser flash method. Experimental results indicate that the through-plane thermal conductivity of the composite is 4.2 W/(m·K) with only 21.4 wt% BN, which is five times higher than that of the composite with randomly oriented BN. Simulation results show that the macro-anisotropic structure of the composite (caused by the selective distribution of BN) as well as the micro-anisotropic structure (caused by the orientation structure of BN) both play critical roles in spreading heat along the specified direction. Therefore, as-obtained composites with double anisotropic structures possess great potential for the application inefficient and controllable thermal management in various fields.

Broadband photoinduced electron/energy transfer RAFT (PET-RAFT) polymerization was achieved by Au/g-C3N4 complex photocatalysts.

Based on the DFT‐level calculated molecular volume (V mol ) of pyrrole and its liquid density, pyrrole manifests the highest liquid density coefficient LD c (defined as [V mol • density • 0.6023]/FW) value of 0.7. Normal liquids have LD c < 0.63. This very high LD c is due to the strong N‐H … π interactions in solution and hence pyrrole can be considered to be a pseudo‐crystalline liquid. When trapped inside the confined space of the crystalline sponge a reorientation of the N‐H … π interaction is observed leading to specific cyclic N‐H … π tetramers and N‐H … π dimers, verified by single crystal X‐ray crystallographic and computational methods. These tetramers are of the same size as four pyrrole molecules in the solid‐state of pyrrole, yet the cyclic N‐H … π intermolecular interactions are circularly oriented instead of the linear zig‐zag structure found in the X‐ray structure of a solid pyrrole. The confinement thus acts as an external driving force for the tetramer formation. peerReviewed

The process of mining filling, when the slurry is transported to the goaf by the filling pipeline, is very important to find the location and size of the caking in the filling pipeline in time for the safe and stable operation of the mine filling pipeline. It is an important research work to detect different flow patterns after two-dimensional section reconstruction in closed filling pipeline based on ECT (electrical capacitance tomography) visualization method. Slurry flow in pipeline is regarded as a two-phase flow, and the multishape distribution was reconstructed into images by ECT and intelligently recognized by broad learning system (BLS) algorithm. BLS is a feedforward neural network with few optimization parameters and fast training speed. In this paper, three features of two-phase sample images, the number of regional blocks, the roundness of regional blocks, and barycenter of regional blocks, are combined with network structure of BLS to recognize different flow patterns. Through the simulation, the recognition accuracy of two-phase fillback image is more than 99%. This conclusion indicates the effectiveness of BLS to predict different two-phase flow patterns; it also provides a new solution for the pattern recognition of the flow pattern in the mining filling pipeline.

Gold (Au) nanocrystals were recognized to be a remarkable photocatalyst because of their strong localized surface plasmon resonance (LSPR). Here Au nanocrystals were exploited as plasmonic photocatalysts for photo-regulated reversible addition–fragmentation chain-transfer (RAFT) polymerization. In addition to the well-controlled RAFT polymerization process under a broadband of light (from visible to the near-infrared region), the dimension (0-D nanospheres and 1-D nanorods) and aspect ratio (length/width) of the nanocrystals exhibited a remarkable effect on the polymerization rate under different light sources. The reduction of plasmon damping leads to a relatively long-lived region of high electron density on the surface of the Au nanorods, which can accelerate charge transfer and induce a higher polymerization rate. Moreover, the aspect ratio related to the longitudinal absorption band of the Au nanorods may provide more flexible choices for advanced macromolecular photosynthesis for potential in biomedical and industrial applications.

The water-stopping efficiency of cofferdams for pile caps is an important indicator with direct influ- ence to the quality and durability of the pile-pouring process. In recent years, a new technique fea- turing flexible capsules serving as waterstops has been introduced, but is still in experimental stage. This thesis, taking the water-stopping construction programme of underwater PC houses of the J. P. Magufuli Bridge project in Tanzania as background, analyzed the two existed types of flexible water- stopping construction methods, id est the integral and separate structures, and studied on measures for improving the flexible water-stopping construction techniques and optimizing the rubber cap- sule waterstops, in the hope of providing references and, possibly, inspirations for similar projects in the future.

Silver nanomaterials have attracted a great deal of interest due to their broad-spectrum antimicrobial activity. However, it is still challenging to balance the high antibacterial efficiency with low damage to biological cells of silver nanostructures, especially when the diameter decreases to less than 10 nm. Here, we developed a new type of Ag nanohybrid material via a unimolecular micelle template method, which presents amazing antibacterial activities and almost noncytotoxicity. First, water-soluble multiarm star-shaped brushlike copolymer α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 was precisely synthesized and its micelle behavior in different solvents was revealed. Then, nanocrystal clusters assembled by Ag grains (Ag@Template NCs) were prepared through an in situ redox route using the unimolecular micelle of α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 as the soft template, AgNO3 as a precursor, and tetrabutylammonium borohydride (TBAB) as the reducing agent. The overall size of the achieved Ag@Template NCs is controlled by the template structure at around 40 nm (Dh in DMF), and the size of the Ag grain can be easily regulated from ∼1 to ∼5 nm by adjusting the feeding ratio of AgNO3/acrylic acid (AA) units in the template from 1:10 to 1:1. Benefitting from the structural design of the template, all Ag@Template NCs prepared here exhibit excellent dispersibility and chemical stability in different aqueous environments (neutral, pH = 5.5, and 0.9% NaCl physiological saline solution), which play a crucial role in the long-term storage and potential application in a complex physiological environment. The antibacterial and cytotoxicity tests indicate that Ag@Template NCs display much better performance than Ag nanoparticles (Ag NPs), which have a comparable overall size of ∼25 nm. The inhibitory capability of Ag@Template NCs to bacteria strongly depends on the grain size. Specifically, the Ag@Template-1 NC assembled by the smallest grains (1.6 ± 0.3 nm) presents the best antibacterial activity. For E. coli (-), the MIC value is as low as 5 μg/mL (0.36 μg/mL of Ag), while for S. aureus (+), the value is around 10 μg/mL (0.72 μg/mL of Ag). The survival rate of L02 cells and lactate dehydrogenase assay together illustrate the low cytotoxicity possessed by the prepared Ag@Template NCs. Therefore, the proposed Ag@Template NC structure successfully resolves the high reactivity, instability, and fast oxidation issues of the ultrasmall Ag nanoparticles, and integrates high antibacterial efficiency and nontoxicity to biological cells into one platform, which implies its broad potential application in biomedicine.

An unconventional but robust route to fabricate highly pure α-Al2O3 colloidal nanocrystals with tunable surface chemistry and dimensions was introduced based on semi-aromatic polyamide (PA6Py) with pyridine rings as a functional matrix. The surface ligands of α-Al2O3 nanocrystals can be tuned by choosing different carboxyl-terminated polymers (e.g., PS and PEO).