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Highlights: [•] Porous carbons were prepared using endothelium corneum gigeriae galli as precursor. [•] Surface and structural properties strongly depend on carbonization temperatures. [•] Resultant carbons possess nitrogen heteroatom and high surface areas. [•] ECGG-900 sample exhibits excellent electrochemical capacitive performances. [ABSTRACT FROM AUTHOR]

Abstract: In this study, highly hierarchically porous NiO nanosheet arrays were synthesized on glass by a hydrothermal growth method. The effects of temperature and the reactant concentrations on the morphology of the nanosheets were examined. SEM revealed uniform and hierarchical porous NiO nanosheets at 50mM of a nickel nitrate hexahydrate solution at 90°C in 2h. After heat treatment in oxygen at 450°C for 1h, the resistivity of the annealed NiO nanosheet samples was five orders of magnitude lower than the as-prepared samples. In addition, the resistivity of the nanosheet arrays decreased significantly with increasing reactant concentration. The hierarchically porous nanosheets synthesized under optimal conditions were 200–400nm in thickness and 6–8μm in height. These nanosheets might have potential electrochromic applications. [Copyright &y& Elsevier]

Smooth and rough porous copper fiber sintered sheets, employed here as wicks for loop heat pipes for the first time, were fabricated using a low-temperature solid-phase sintering method. The capillary performance of these porous copper fiber sintered sheets were analyzed and discussed. The influence of the surface morphology, filling ratio, and working fluid on the thermal resistance, evaporator wall temperature, and start-up time of the loop heat pipes were investigated. The results showed that the capillary pumping amount of working fluid for both smooth and rough porous copper fiber sintered sheets initially increases rapidly, and then gradually attains a stable state. The curve of the capillary pumping amount of working fluid can be described as a function that increases exponentially over time. When rough porous copper fiber sintered sheets are used as wicks and deionized water is used as the working fluid, the capillary pumping amount is maximized. Compared to smooth porous copper fiber sintered sheets, loop heat pipes with rough porous copper fiber sintered sheets exhibit a shorter start-up time, lower thermal resistance, and lower evaporator wall temperature. For a filling ratio in the range of 15–45%, loop heat pipes with rough porous copper fiber sintered sheets and a 30% filling ratio show lower thermal resistance and a lower evaporator wall temperature. Ultimately, the use of deionized water as the working fluid with a 30% filling ratio enables loop heat pipes with rough porous copper fiber sintered sheets to be stably operated at a heat load of 200 W. [ABSTRACT FROM AUTHOR]

A novel porous copper fiber sintered felt (PCFSF) as catalyst support is fabricated to construct the methanol steam reforming microreactor for hydrogen production. In this study, the heat and mass transfer properties of PCFSF with different porosities is experimentally investigated. The results show that the PCFSF with different porosities exhibits good uniform heat transfer. The thermal conductivity is decreased with increasing porosity in the porosity range of 70–90%. With lower gas feed rate, no great change of the pressure drop is observed. However, larger pressure drop is produced with the higher gas feed rates. Moreover, we found that the resident time in the PCFSF is gradually decreased with increasing porosity. Much longer resident time is obtained when the lower gas feed rate is selected. The PCFSF with 80% porosity as catalyst support presents better reaction performance because of the enhancement of heat and mass transfer resulting from the unique porous structure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Both three- and four-point bending setup were established. [•] Similar three stages in three- and four-point bending fracture process were observed. [•] The bending strength was decreased with increasing porosity. [•] Higher sintering temperature produced higher bending strength. [•] The extension of holding time slightly affected the bending strength. [Copyright &y& Elsevier]

Abstract: A novel porous metal fiber sintered sheet (PMFSS) with high porosity was fabricated by the solid-state sintering method of copper fibers. In this study, the shear experiments were conducted to investigate the effect of porosity and sintering parameter on the shear properties of PMFSS. The typical shear stress–strain plot of PMFSS was obtained based on a larger number of shear test results. The shear fracture process of PMFSS was then divided into three steps: linear elastic stage, plastic deformation stage, and shear fracture stage. The shear strength was found to be decreased with increasing porosity ranging from 70% to 90% when the PMFSS was produced under the same sintering parameter. Moreover, the influence of sintering parameter on shear strength of PMFSS was also investigated. Our experimental results showed that the increase of the sintering temperature or holding time would give rise to the increase of shear strength of PMFSS. [Copyright &y& Elsevier]

Abstract: A novel porous metal fiber sintered sheet (PMFSS) with three-dimensional reticulated structure was fabricated by using solid-state sintering method of copper fibers. Uniaxial compressive test was carried out to investigate the effects of porosity and manufacturing parameters on the compressive properties of PMFSS. During the compressive process, it was found that the PMFSS initially exhibited short-term elastic deformation, and then quickly entered into the compact densification deformation stage. The stress–strain plots showed no obvious yield stage in the whole uniaxial compressive process. Under given stress, the PMFSS with higher porosity exhibited higher strain, hence implying lower effective stiffness. Additionally, our results showed that higher sintering temperature or longer sintering time would soften the PMFSS. [Copyright &y& Elsevier]