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Up‐to‐date laser‐driven projection technology puts an urgent demand for green phosphor with stringent requirements on its performance. Herein, by virtue of a new architecture design based on CsPbBr3‐glass nanocomposite, i.e., CsPbBr3 glass ceramic film sintered on sapphire plate, the application availability of this famous green‐emitting phosphor is demonstrated in laser‐driven projection. The mono‐dispersed perovskite CsPbBr3 nanostructure in amorphous glass matrix and the negligible thermal corrosion during co‐sintering with low‐melting‐glass ensure good luminescent properties. The robust glass host and the carried sapphire substrate with high thermal conductivity contribute to good resistances to thermal shock, moisture, and blue laser irradiation. It is revealed that the thermal accumulation effect is relieved due to the pulsed excitation of rotatory "phosphor wheel," and so the luminescence saturation threshold gets increased. The constructed prototype lighting source yields a low étendue of ≈0.41 mm2, a wide color gamut of 128.4% NTSC (95.9% Rec. 2020), and a moderate luminous flux of 174 lm. The present work highlights an unprecedented design that makes the seemingly impossible application of CsPbBr3 come true. [ABSTRACT FROM AUTHOR]

Salt structures are high potential targets for oil and gas exploration. However, large-scale salt domes with irregular surfaces pose significant challenges for velocity model building. For full waveform inversion, in the absence of a high-fidelity initial model, the success of the inversion depends on low-frequency seismic data, which are scarce in the exploration data sets. This paper presents a new idea to solve the problem of salt structure velocity modelling. First, we propose an envelope-based full-band seismic data reconstruction algorithm. The smoothness of envelope is used to segment the events in seismic data, and the phase independence of envelope is used for the identification of the seismic event's arrival-time to obtain the apparent reflection sequences of the subsurface. Full-band seismic data are obtained by convolving the apparent reflection sequence with full-band source. Window averaging function and threshold strategy are used to ensure the accuracy of seismic event segmentation and the stability of the algorithm when dealing with noisy data. Then the multiscale reflection waveform inversion based on reconstructed data is proposed for salt structure velocity building. The numerical experiment results of the Sigbee2A model demonstrate the performance of the inversion algorithm in the case where the seismic data lack low-frequency components and contain noise. The limitations of the algorithm have also been analysed and studied. [ABSTRACT FROM AUTHOR]

A special admixture RD-EC100 for planting concrete was prepared by solid polycarboxylic superplasticizer S:6%, fly ash FA:10%, early strength agent E:4%, superfine powder X:77%, air entraining agent Y:0.1% and pH regulator P:2.9%. In addition, the performance indexes of concrete strength, porosity and pH of different varieties of cement and different strength grades were determined, and compared with commercially available product performance. The results show that the cement has good compatibility, the performance of the admixture is better than the commercial products, and the recommended optimum dosage is 4%. [ABSTRACT FROM AUTHOR]

In this work, W18O49/WOx/W dendritic nanostructures were facilely fabricated by a one-step thermal evaporation method, into which a reduction process at a temperature as high as 1250 °C was deliberately inserted. In the dendritic nanostructure, W18O49 nanowires acted as tree trunks, W nanoparticles acted as fruits grown on the tree trunks and amorphous WOx layers acted as self-assembly bonds between them. In the reduction process, dangling bonds and defects were expected in this integrated nanostructure, greatly enhancing its optical absorption covering the full spectrum (200–2500 nm). High-performance degradation of methyl orange using these dendritic nanostructures under vis-NIR irradiation (with wavelength ≥550 nm) was achieved for the first time, with good cycling durability in view of no deterioration after ten reaction cycles, which stemmed from their enhanced optical absorption and boosted the separation of photoexcited carriers distinctively by the interfacial tunneling effect of electrons owing to the existence of the two-dimensional WOx bond layer (1–2 nm). This dendritic nanostructure holds great promise for waste-water treatment and organic dye degradation. [ABSTRACT FROM AUTHOR]

A novel three-dimensional ball-flower-like g-C3N4/NiO (GN) photocatalyst was firstly fabricated by a simple two-step calcination method for enhanced degradation capability. Our investigation focuses on the construction of p–n heterojunction and specific ball-flower-like structure to overcome limitations of single-component semiconductors, such as low surface area, poor light response and fast recombination of the photogenerated electrons and holes. Detailed photocatalytic experiments revealed that the novel ball-flower-like GN (50%) exhibited much higher activity for the removal of TC and Cr6+ than single g-C3N4, NiO and traditional layered GN. The trapping experiments proved that the superoxide radicals ( · O 2 - ), holes (h+) and electrons (e−)were the main active species in the photodegradation process. Moreover, three different degradation pathways and fourteen intermediate products of TC were also determined by the LC/MS analysis and these intermediates could be further degraded completely into CO2, H2O, NH 4 + , carboxylic acids and any other inorganic intermediates. These results will benefit the fabrication of other 3D p–n heterojunction photocatalysts and their potential application in treatment of organic pollutants. [ABSTRACT FROM AUTHOR]

In order to study the bond properties of BFRP Bars and insulation wall panel protective layer concrete after plastic film steaming the design method of orthogonal experiment was adopted considering the influence of three factors which was concrete strength protective layer thickness and bond length under different levels. BFRP bars concrete specimens were steamed for 8 h and then were cured in standard for 3 d and 28 d respectively and then the center pulling out experiment was tested. The change rule of bond strength with influencing factors was studied and multiple linear regression method was used to regress the bond strength of BFRP reinforced concrete specimens for 3d and 28 d respectively. The results show that the bond length is the most significant factor influencing the bond strength of specimens and the strength of concrete takes second place the thickness of protective layer is even less and the variation rule of 3 d and 28 d is consistent. The optimum combination of the bond strength was that the strength grade of concrete was C30 the concrete cover thickness was 40 mm and the bond length was 20 mm. The regression formula provides the theoretical basis for the bond strength of different concrete strength protective layer thickness and bond length of specimens in varied ages. [ABSTRACT FROM AUTHOR]