We propose a novel fluorescent adhesive-assisted biomimetic mineralization strategy, based on which 1 wt% of sodium fluorescein and 25 wt% of polyacrylic acid stabilized amorphous calcium phosphate (PAA-ACP) nanoparticles were incorporated into a mild self-etch adhesive (Clearfil S3 Bond) as a fluorescent mineralizing adhesive. The characterization of the PAA-ACP nanoparticles indicates that they were spherical particles clustered together, each particle with a diameter of approximately 20-50 nm, in a metastable phase with two characteristic absorption peaks (1050 cm-1 and 580 cm-1). Our results suggest that the fluorescent mineralizing adhesive was non-cytotoxic with minimal esthetic interference and its fluorescence intensity did not significantly decrease within 6 months. Our data reveal that the fluorescent mineralizing adhesive could induce the extra- and intra-fibrillar remineralization of the reconstituted type I collagen, the demineralized enamel and dentin substrate. Our data demonstrate that a novel fluorescent adhesive-assisted biomimetic mineralization strategy will pave the way to design and produce anti-carious materials for the prevention of dental caries.

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Rapid biomimetic intrafibrillar mineralization of collagen was induced by polyelectrolyte–calcium complexes as a pre-precursor.

Self-assembled nanostructure arrays integrating the advantages of the intrinsic characters of nanostructure as well as the array stability are appealing in advanced materials. However, the precise bottom-up synthesis of nanostructure arrays without templates or substrates is quite challenging because of the general occurrence of homogeneous nucleation and the difficult manipulation of noncovalent interactions. Herein, we first report the precisely manipulated synthesis of well-defined louver-like P-doped carbon nitride nanowire arrays (L-PCN) via a supramolecular self-assembly method by regulating the noncovalent interactions through hydrogen bond. With this strategy, CN nanowires align in the outer frame with the separation and spatial location achieving ultrastability and outstanding photoelectricity properties. Significantly, this self-assembly L-PCN exhibits a superior visible light-driven hydrogen evolution activity of 1872.9 μmol h−1 g−1, rendering a ~ 25.6-fold enhancement compared to bulk CN, and high photostability. Moreover, an apparent quantum efficiency of 6.93% is achieved for hydrogen evolution at 420 ± 15 nm. The experimental results and first-principles calculations demonstrate that the remarkable enhancement of photocatalytic activity of L-PCN can be attributed to the synergetic effect of structural topology and dopant. These findings suggest that we are able to design particular hierarchical nanostructures with desirable performance using hydrogen-bond engineering.

This laboratory study examined the influence of particle size and density, and channel velocity on the spatial deposition pattern around an emergent (extending through the entire water depth), circular patch of model vegetation located at the center of a channel. Three flow conditions and three particles of different size and density were considered. Across all particle and velocity conditions, three basic deposition patterns were observed: (1) high deposition in the patch wake and low deposition in the zones adjacent to the patch; (2) high deposition in both the wake and adjacent zones; and (3) low deposition in both the wake and adjacent zones. The observed deposition pattern correlated with the ratio of channel shear velocity (u Ã Þ to critical shear velocity (u Ãc Þ: Specifically, for u à =u Ãc < 0:7 or u à =u Ãc > 3, the deposition was high (or low, respectively) over the entire channel with little difference between the wake and adjacent regions. In contrast, for 0:7 < u à =u Ãc < 3 divergence in net deposition between the wake and the adjacent zones occurred, with higher net deposition in the wake and lower net deposition in the adjacent zones. The peak divergence was observed at u à =u Ãc 51:6. The deposition patterns were more closely correlated with the ratio u à =u Ãc than with w s =u à (with w s the particle settling velocity), suggesting that the spatial variation in net deposition was driven by resuspension (associated with u Ãc ) and not settling (associated with w s ).

It is of importance but highly challenging for copper (Cu)-based catalysts to maintain the structure of active Cu sites under working conditions. Herein, the commercial Cu/ZnO/Al2O3 catalyst was confined in the mesoporous SiO2–Al2O3 shell via hydrothermal synthesis (CZAS@SA) for selective hydrogenation of CO2 to dimethyl ether (DME) and methanol. CZAS@SA catalysts exhibited higher intrinsic activity for the formation of DME and methanol and much lower intrinsic activity for CO formation than Cu/ZnO/Al2O3. Thus, the total selectivity of DME and methanol was enhanced from 9.1 to 63.3 mol %. In situ X-ray photoelectron spectroscopy/X-ray absorption fine structure/high-resolution transmission electron microscopy (XPS/XAFS/HRTEM) results and catalytic measurements indicated that the metallic Cu­(Cu0)–ZnO interface was the active site for methanol formation. Commercial Cu/ZnO/Al2O3 underwent a separation of Cu0 and ZnO phases during the reaction, and this phase separation caused agglomeration of Cu0 and shrinking of the active Cu0–ZnO interface, which aggregated CO formation. The active Cu0–ZnO interface in CZAS@SA was preserved due to the confinement effect of the shell, which improved methanol selectivity.

A surface plasmon resonance (SPR) chemical sensor comprising microstructured optical fiber (MOF) is designed for refractive index (RI) sensing in the visible to near-infrared (0.42-1.60 µm) region (NIR) as well as detection of gas-liquid pollutants. To realize mode coupling and facilitate manufacturing, gold with inert and plasmonic properties and an analyte sensing layer are introduced to the external surface of the MOF. The sensor is analyzed by the full-vector finite element method (FEM) and the wavelength and amplitude interrogation methods are adopted to evaluate the sensing characteristics. Our analysis reveals a maximum wavelength sensitivity (WS) of 15,000 nm/RIU, amplitude sensitivity (AS) of 1,603.37 RIU-1, and resolution (R) of 6.67×10−6 RIU in the determination of analyte RIs spanning an ultra-wide range between 1.00 and 1.45. Furthermore, the figure of merit (FOM) and signal-to-noise ratio (SNR) of the sensor are 295.01 RIU−1 and 2.95, respectively. On account of its simple structure, low cost, and industrial compatibility, this multi-functional sensor has tremendous potential in the chemical industry, environmental monitoring, and safety control such as harmful gas monitoring, industrial wastewater and domestic sewage detection.

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