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The reasons for the local adhesion differences of the hot-dip galvanized coating on high-strength angle steel were analyzed by means of scanning electron microscopy (SEM) and optical microscopy (OM)， and the microstructures of the coating and steel base in the good bonding area and poor bonding area of galvanized angle steel were compared. Results showed that: (1) The adhesion difference of the coating on steel substrate were closely related to the microstructure of the caoting. The coating area with good bonding strength was characterized with small column-like or lumpy ζ phase and discontinuous δ phase. When the coating suffering hammering， the hammered area was generally in the form of pits， and the alloy layer was extruded and deformed without cracks. The coating area with poor bonding strength consisted of a coarse columnar or bulky ζ phase and a continuous and thick δ layer， which would be stripped from the substrate interface when the coating suffering hammering. (2) Moreover， the surface microstructure of steel substrate had influence on the galvanized coating. During galvanizing， equilibrium structure was in favor of the diffusion of Fe， facilitating the growth of ζ and limiting the growth of δ， which was beneficial to the bonding between coating and substrate. However， the appearance of non-equilibrium structure could inhibit the diffusion of Fe， lower the growth of ζ and benefit to the growth of δ because of the solution strengthening，lattice distortion and internal residual stress，which was harmful for the bonding strength of hot-dip galvanized coating.

Dry eye disease (DED) is a growing public health concern affecting millions of people worldwide and causing ocular discomfort and visual disturbance. Developing its therapeutic drugs based on animal models suffer from interspecies differences and poor prediction of human trials. Here, we established long‐term 3D human corneal epithelial organoids, which recapitulated the cell lineages and gene expression signature of the human corneal epithelium. Organoids can be regulated to differentiate ex vivo, but the addition of FGF10 inhibits this process. In the hyperosmolar‐induced DED organoid model, the release of inflammatory factors increased, resulting in damage to the stemness of stem cells and a decrease in functional mucin 1 protein. Furthermore, we found that the organoids could mimic clinical drug treatment responses, suggesting that corneal epithelial organoids are promising candidates for establishing a drug testing platform ex vivo. In summary, we established a functional, long‐term 3D human epithelial organoid that may serve as an ex vivo model for studying the functional regulation and disease modelling. [ABSTRACT FROM AUTHOR]

Coal mining generally induces stress concentration around the goaf range, and the hard roof undergoes fracture and instability when the stress exceeds the tensile strength. It is crucial to investigate the mechanical behavior of the hard roof and determine the corresponding influencing factors of fracture. However, the roof load is treated as the normal distribution function or simple piecewise linear function in the existing research, which makes the model applicable only to specific load forms. For this purpose, the eight-segment linear function is used in this study to subdivide the supercharged load acting on the roof based on different foundation conditions, which can help one to avoid complex calculations of mechanical behavior and ensure proximity to the actual load. The coal seam in front of the coal wall is regarded as an elastic foundation, and the deflection curve equation is established by analyzing the force on the roof. The internal force and deformation of the hard roof are obtained before the initial and periodic fractures. The accuracy of this model is verified by comparing it with other models in the literature. The results of parameter sensitivity analysis indicate that with the increase of foundation stiffness, roof thickness, and support resistance, the deflection and bending moment significantly decrease. The deflection, bending moment, and shear force are generally positively correlated with goaf length. When the roof is thin and the coal seam is soft, the initial fracture position occurs at the midspan, while the periodic fracture always occurs inside the coal wall. The fracture position gradually moves toward the coal wall with the increase of coal seam stiffness for both the initial and the periodic fractures. The research results are helpful to understand the internal force and deformation mechanism of the hard roof and provide a valuable theoretical basis for predicting the fracture mode of the roof. [ABSTRACT FROM AUTHOR]

P. santalinus waste powders were utilized to prepare the aqueous extracts for the dyeing of wool fabric. The extraction and dyeing processes of P. santalinus were optimized for obtaining the dyed fabric with high color strength and flavonoids content. The antibacterial, antioxidant and aqueous Cr(VI) removal capacity of the dyed fabric was then examined and compared with other two plant (P. tinctorius and Lycium ruthenicum Murray) material extract dyed wool fabrics. The results indicated that the addition of ethanol in aqueous solvent could increase the content of colorants and flavonoid compounds in P. santalinus extract when soxhlet apparatus was used. The highest extraction effectiveness of P. santalinus was achieved at ethanol concentration of 80%. High dyeing temperature or low pH level caused an almost linear increment in color strength and flavonoid content of the dyed fabric. Optimum dyeing of wool fabric could be conducted when 35 mL of P. santalinus extract was used to prepare 100 mL of dyeing bath. The dyed fabric not only showed unique color, but also presented better antibacterial, antioxidant and Cr(VI) removal capacity, which were higher than those of the other two dyed fabrics. Increasing color strength or flavonoid content could enhance their functionalities. Pterocarpus santalinus waste extract was used to prepare wool fabric for healthy and environmental care using a dyeing process. [ABSTRACT FROM AUTHOR]