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The ultimate capability of light-electricity conversion of a laser with different operation modes in a typical photovoltaic (PV) cell was investigated for the technologic concept of laser power transmission (LPT). The quasi-linear correlation between the maximum allowable laser power density and the pulsed laser power percentage (PPP) of the combined dual lasers was found experimentally on a tri-junction GaAs PV cell. At the same time, the patterns of thermomechanical damage in the PV cells were characterized. The physical mechanism on the difference in the light-electricity conversion ability for a multi-pulse (MP) laser and a continuous wave (CW) laser was revealed by the coupled model on thermal diffusion and the carrier transport.

Copper is a trace element necessary for the normal functioning of organisms, but excessive copper contents may be toxic to the heart. The goal of this study was to investigate the role of excessive copper accumulation in mitochondrial damage and cell apoptosis inhibition. In vivo, the heart copper concentration and cardiac troponin I (c-TnI) and N-terminal forebrain natriuretic peptide (NT-pro-BNP) levels increased in the copper-laden model group compared to those of the control group. Histopathological and ultrastructural observations revealed that the myocardial collagen volume fraction (CVF), perivascular collagen area (PVCA) and cardiomyocyte cross-sectional area (CSA) were markedly elevated in the copper-laden model group compared with the control group. Furthermore, transmission electron microscopy (TEM) showed that the mitochondrial double-layer membrane was incomplete in the copper-laden model groups. Furthermore, cytochrome C (Cyt-C) expression was downregulated in mitochondria but upregulated in the cytoplasm in response to copper accumulation. In addition, Bcl-2 expression decreased, while Bax and cleaved caspase-3 levels increased. These results indicate that copper accumulation in cardiomyocyte mitochondria induces mitochondrial injury, and Cyt-C exposure and induces apoptosis, further resulting in heart damage., (Copyright © 2022. Published by Elsevier Inc.)

Microstructure dependence of effective thermal conductivity of the coating was investigated to optimize the thermal insulation of columnar structure electron beam physical vapor deposition (EB-PVD coating), considering constraints by mechanical stress. First, a three-dimensional finite element model of multiple columnar structure was established to involve thermal contact resistance across the interfaces between the adjacent columnar structures. Then, the mathematical formula of each structural parameter was derived to demonstrate the numerical outcome and predict the effective thermal conductivity. After that, the heat conduction characteristics of the columnar structured coating was analyzed to reveal the dependence of the effective thermal conductivity of the thermal barrier coatings (TBCs) on its microstructure characteristics, including the column diameter, the thickness of coating, the ratio of the height of fine column to coarse column and the inclination angle of columns. Finally, the influence of each microstructural parameter on the mechanical stress of the TBCs was studied by a mathematic model, and the optimization of the inclination angle was proposed, considering the thermal insulation and mechanical stress of the coating.