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Nondestructive testing (NDT) for damage in thermal barrier coatings (TBCs) is significant for the safety guarantee of gas turbine blades. As a new NDT technology, electromagnetic acoustic transducer (EMAT) is widely applied for NDT of conductive structural components due to its advantages of coupling-free and high adaptability. In this paper, numerical simulations are conducted to study the wave propagation and interaction with delamination defects in TBCs inspected with a Rayleigh wave EMAT of the Lorentz force mechanism. Based on the numerical results, the wave structure in TBC, wave conversion at delamination defect, time domain EMAT signals, and its B-scan images are evaluated and the feasibility of Rayleigh wave EMAT to inspect delamination in TBCs was theoretically clarified. [ABSTRACT FROM AUTHOR]

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The Hollow Cathode Gas Flow Sputtering (GFS) provides special plasma conditions and is of extensive interest as a more affordable alternative to the high vacuum sputtering techniques. In the case of the tubular cathode a circular outlet symmetry stipulates homogeneity issues for both metallic and reactive deposition regimes. Using the results of Direct Simulation Monte Carlo (DSMC), we propose an external coaxial attachment which is manufactured and examined in a nozzle and a diffuser positioning. The impact on the homogeneity of Ti and  TiO 2  films is examined using profilometry and spectral ellipsometry. Our results demonstrate that the use of the nozzle attachment significantly enhances film homogeneity from about 3  cm 2  to more than 12  cm 2 . It also secures better process control in terms of oxygen stoichiometry and film thickness. Some crucial general issues of the reactive GFS process are discussed. [ABSTRACT FROM AUTHOR]

In this paper, the simulated nuclear waste was successfully immobilized by using aluminosilicate glass made from natural granite material without other additive agents. The neodymium-doped matrix's phase composition, microstructure, element distribution, hardness, density, indentation fracture toughness, and aqueous durability were analyzed. The results show that the samples with a neodymium content of 10 wt.% are fully vitrified and reach the maximum neodymium solubility. The silicate tetrahedra of glass networks mainly exist in sheets (Q3) and frame (Q4) units. Neodymium oxide acts as a glass modifier and destroys the sheet form and may precipitate metal elements in the matrix, resulting in a Vickers hardness of up to 8.17 GPa for this aluminosilicate glass. However, the indentation fracture toughness decreases. Moreover, NRNd is about 10−7 ~ 10−8 g·m−2·d−1 during the 28-day aqueous durability test, indicating its excellent aqueous durability. This work provides a new idea for immobilizing radionuclides via glass. [ABSTRACT FROM AUTHOR]

In this paper, the simulated nuclear waste was successfully immobilized by using aluminosilicate glass made from natural granite material without other additive agents. The neodymium-doped matrix's phase composition, microstructure, element distribution, hardness, density, indentation fracture toughness, and aqueous durability were analyzed. The results show that the samples with a neodymium content of 10 wt.% are fully vitrified and reach the maximum neodymium solubility. The silicate tetrahedra of glass networks mainly exist in sheets (Q3) and frame (Q4) units. Neodymium oxide acts as a glass modifier and destroys the sheet form and may precipitate metal elements in the matrix, resulting in a Vickers hardness of up to 8.17 GPa for this aluminosilicate glass. However, the indentation fracture toughness decreases. Moreover, NRNd is about 10−7 ~ 10−8 g·m−2·d−1 during the 28-day aqueous durability test, indicating its excellent aqueous durability. This work provides a new idea for immobilizing radionuclides via glass. [ABSTRACT FROM AUTHOR]

Coseismic landslides pose a significant threat to the sustainability of both the natural environment and the socioeconomic fabric of society. This escalation in earthquake frequency has driven a growing interest in regional-scale assessment techniques for these landslides. The widely adopted infinite slope model, introduced by Newmark, is commonly utilized to assess coseismic landslide hazards. However, this conventional model falls short of capturing the influence of rock mass structure on slope stability. A novel methodology was previously introduced, considering the roughness of potential slide surfaces on the inner slope, offering a fresh perspective on coseismic landslide hazard mapping. In this paper, the proposed method is recalibrated using new datasets from the 2013 Lushan earthquake. The datasets encompass geological units, peak ground acceleration (PGA), and a high-resolution digital elevation model (DEM), rasterized at a grid spacing of 30 m. They are integrated within an infinite slope model, employing Newmark's permanent deformation analysis. This integration enables the estimation of coseismic displacement in each grid area resulting from the 2013 Lushan earthquake. To validate the model, the simulated displacements are compared with the inventory of landslides triggered by the Lushan earthquake, allowing the derivation of a confidence level function that correlates predicted displacement with the spatial variation of coseismic landslides. Ultimately, a hazard map of coseismic landslides is generated based on the values of the certainty factor. The analysis of the area under the curve is utilized to illustrate the improved effectiveness of the proposed method. Comparative studies with the 2014 Ludian earthquake reveal that the coseismic landslides triggered by the 2013 Lushan earthquake predominantly manifest as shallow rock falls and slides. Brittle coseismic fractures are often associated with reverse seismogenic faults, while complaint coseismic fractures are more prevalent in strike–slip seismogenic faults. The mapping procedure stands as a valuable tool for predicting seismic hazard zones, providing essential insights for decision-making in infrastructure development and post-earthquake construction endeavors. [ABSTRACT FROM AUTHOR]

In this study, an explicit time integration scheme based on cubic B-spline interpolation strategy and momentum corrector is extended for structural seismic response analysis. The acquisition strategy for the required seismic load is provided. The cubic B-spline-based scheme with moment corrector is generalized for the nonlinear hysteresis system. The analysis shows that the explicit scheme has more desirable stability and accuracy properties than other competitive schemes. The effectiveness of the scheme is demonstrated by the linear and nonlinear numerical examples. [ABSTRACT FROM AUTHOR]