The particle size distribution of the typical granite residual soil which usually has considerable contents of sand, indicates that the soil may have transitional behavior, then isotropic consolidation tests and shear tests of various stress paths were performed. Test results show that: the mechanical behavior of the granite residual soil can not be described by the critical state framework. The consolidation lines of soils with different initial void ratios in the v-lnp′ plane can not be come together to form the unique Normal Consolidation Line (NCL), and the unique Critical State Line (CSL) can not be identified neither during shearing. The states of soils in consolidation and shearing are dominated by the initial void ratio (initial density), and this domination could not be erased by high confining pressure or shearing stress, which is a typical transitional behavior. The consolidation lines and the corresponding critical state lines of soils with different initial void ratios in the v-lnp′ plane are parallel. The distance between each normal consolidation line and its corresponding critical state line is found to be fixed, and the distance is not influenced by initial void ratio.

Bubbles generated during the oxygen evolution reaction (OER) in water splitting readily adhere to the electrode surface, thereby impeding contact between the electrolyte and the active sites, thereby increasing the overpotential. Consequently, it is imperative to elucidate the bubble release behavior and engineer electrodes that facilitate faster bubble release. In this study, inspired by the wood stem of the Norway spruce, we synthesized a gradient nanoporous high-entropy oxide (GNP-HEO) electrode with a controllable pore size. The GNP-HEO, featuring a well-controlled gradient in pore size, is achieved through a straightforward strategy combining selective laser melting with selective phase dissolution. This unique gradient nanoporous structure not only facilitates bubble release but also diminishes the bubble shielding effect in OER, thereby enhancing electrocatalytic performance. The affect interaction of Al, Co, Cr, Fe, and Ni, coupled with the gradient nanoporous structure, yields exceptional OER performance, evidenced by an overpotential of 250 mV at a current density of 50 mA/cm² and a Tafel slope of 38.0 mV/dec in 1 M KOH. Density functional theory calculations confirm that the GNP-HEO adheres to the adsorbate evolution mechanism reaction pathway and exhibits significant stability. This work highlights a promising approach for the design and synthesis of high-performance OER electrocatalysts.