We report a novel three-dimentional (3D) porous nano-Ni/Co(OH)2 nanoflake composite film electrode for potential supercapacitor applications with both high power and energy capabilities. The 3D porous nano-Ni film with highly porous nanoramified walls functions as a scaffold to anchor Co(OH)2 nanoflakes to produce a 3D nanoporous metal/hydroxide nanoflake composite electrode. Co(OH)2 nanoflakes with thicknesses of 20 nm are directly electrodeposited on highly conductive 3D porous nano-Ni film prepared via a hydrogen bubble template. Impressively, the Co(OH)2 nanoflake in the composite film exhibits a high specific capacitance of 1920 F g–1 at 40 A g–1, with a corresponding energy density as high as 80 W h kg–1 at a power density of 11 kW kg–1. Moreover, the designed composite film exhibits excellent cycling stability, making it one of the best electrode materials for high-performance supercapacitors. This work demonstrates that the 3D porous nanometal/hydroxide nanoflake composite approach is an effective strategy toward supercapacitors with high energy and power densities.

Plant responses to elevated CO₂ and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO₂ conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO₂ (800 μmol·mol(-1) ) and heat stress (42 °C for 24 h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO₂ remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO₂ significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO₂ and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO₂ -induced heat stress alleviation. The results of this study suggest that elevated CO₂ alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.

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The general governing equation of transverse wave motion in a viscoelastic single-walled carbon nanotube (SWCNT) adhered by surface material is formulated on the basis of the nonlocal elasticity theory and the Kelvin model. The properties of transverse wave propagation in the SWCNT are investigated. The explicit expressions are derived for the frequency and phase velocity of the wave motion. The small scale and surface effects and the influences of structural damping on the properties of wave propagation are elucidated. It is concluded that the frequency and phase velocity of transverse wave propagation in the viscoelastic SWCNT are related to the small scale, surface elasticity, residual surface tension, and structural damping. The small scale and surface effects and the impact of structural damping on the properties of transverse wave propagation are dependent upon the wave number and tube diameter.