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A small energy offset (ΔE < 0.2 eV) between Γ(pxy) and Γ(pz) band orbitals in AB2X2 Zintl compounds enables the realization of band alignment for an increased band degeneracy as well as an enhanced electronic performance. The SrMg2Bi2 Zintl compound has been theoretically illustrated to have a small ΔE, suggesting an approximately inherent convergence of two band orbitals. Therefore, this work is devoted to the revelation of the thermoelectric potential of the SrMg2Bi2 Zintl compound in a broad Hall carrier concentration of 0.3–5 × 1019 cm−3 by Ag-doping at the Sr site. The electrical transport properties can be well predicted by the single parabolic band model with acoustic phonon scattering, which reveals a multi-band transporting behavior in the heavily doped samples due to Fermi level deepening, leading to a significant zT-enhancement. In terms of the model, a peak zT of up to 1.0 is achievable by assuming the amorphous minimum lattice thermal conductivity, which demonstrates this compound as a promising thermoelectric material. [ABSTRACT FROM AUTHOR]

In this era of rapid technological advancement, it is particularly urgent to seek new technological methods for the protection of intangible cultural heritage. The purpose of this study is to develop a digital museum system architecture for intangible cultural heritage and to create an immersive experience utilizing virtual reality and augmented reality technologies in the system’s application layer. The coordinate transformation is realized through visual rendering, the OBB collision detection algorithm is applied to improve the realism of the virtual scene, and the tracking registration algorithm is used to determine in real-time the mapping position of the virtual information to be added in the real spatial coordinates. Taking Sanfangqixiang in F city as an example, the protection effect of intangible cultural heritage and its influencing factors are empirically analyzed. The total score of the comprehensive evaluation of the protection effect of Sanfangqixiang is 4.0156, which is in the grade of “good protection effect”, and its regression model passes the F-test so that the NLC’s cultural confidence positively affects the NLC’s protection (t=5.156, standardized coefficient Beta=0.430, p

Rolling technology based on arc-shaped rollers is a novel method for rapid manufacturing of 3D curved parts. The method uses a pair of arc-shaped rollers (a convex roller and a concave roller) as forming tools, forming an unevenly distributed roll gap. The sheet metal has both transverse bending and longitudinal uneven extension during rolling, so that surface parts with double curvature are processed. The curvature of the formed surface part can be changed by changing the rolling reduction. Changing the vertical distance between the rollers will cause the overall change of the roll gap height, which will inevitably have a great impact on the forming effect of formed 3D curved parts. In this paper, a finite element model and experiment with different rolling reductions was designed; the influence of rolling reduction on the bending deformation and shape accuracy of formed 3D curved parts was studied. The results show that, with the slight increase of rolling reduction (from 0.04 to 0.12 mm), the longitudinal bending deformation of the formed 3D curved part increases significantly, but its transversal bending is almost not affected. When the maximum rolling reduction is 0.04 and 0.06 mm (the corresponding minimum rolling reduction is less than or equal to zero), the shape accuracy of the formed 3D curved parts is not good enough; when the maximum rolling reduction is greater than 0.06 mm (the corresponding minimum rolling reduction is greater than zero), the shape accuracy of the formed 3D curved parts is significantly better. This indicates that, for the rolling of 3D curved parts based on arc-shaped rollers, ensuring that the minimum rolling reduction is greater than zero is the key to ensuring good shape accuracy of the formed 3D curved parts. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) has a wide range of applications in the treatment and prevention of major diseases owing to its high sensitivity and excellent resolution. However, there is still much room for optimization in the readout circuit and fast pulse sampling to further improve the performance of the PET scanner. In this work, a LIGHTENING ® PET detector using a 13 × 13 lutetium-yttrium oxyorthosilicate (LYSO) crystal array read out by a 6 × 6 silicon photomultiplier (SiPM) array was developed. A novel sampling method, referred to as the dual time interval (DTI) method, is therefore proposed to realize digital acquisition of fast scintillation pulse. A semi-cut light guide was designed, which greatly improves the resolution of the edge region of the crystal array. The obtained flood histogram shown that all the 13 × 13 crystal pixels can be clearly discriminated. The optimum operating conditions for the detector were obtained by comparing the flood histogram quality under different experimental conditions. An average energy resolution (FWHM) of 14.3% and coincidence timing resolution (FWHM) of 972 ps were measured. The experimental results demonstrated that the LIGHTENING ® PET detector achieves extremely high resolution which is suitable for the development of a high performance time-of-flight PET scanner. [ABSTRACT FROM AUTHOR]