A novel nanocomposite of Ni nanoparticles loaded on Mg‐doped Al2O3 (Ni/Mg‐Al2O3) was prepared. By photothermocatalytic CO2 reduction with methane (CRM) merely using focused UV‐vis‐IR illumination on Ni/Mg‐Al2O3, high production rates of H2 (rnormalH2, 69.71 mmol min−1 g−1) and CO (rCO, 74.57 mmol min−1 g−1) and an extremely large light‐to‐fuel efficiency (η, 32.9%) are acquired. High rnormalH2 and rCO (51.07 and 59.66 mmol min−1 g−1) and a large η (32.5%) are acquired even by using focused λ > 560 nm vis‐IR illumination. Ni/Mg‐Al2O3 shows good durability for photothermocatalytic CRM due to the side reaction of carbon deposition being enormously inhibited in comparison with a reference catalyst of Ni nanoparticles loaded on Al2O3. The enormous carbon deposition inhibition is ascribed to the presence of a fence of CO2 molecules (strongly adsorbed on Mg‐doped Al2O3) around Ni nanoparticles, which block the polymerization and growth of carbon species to nanofibers by promoting the oxidation of carbon species formed by CH4 dissociation. The high photothermocatalytic activity of Ni/Mg‐Al2O3 arises from efficient light‐driven thermocatalytic CRM. A photoactivation is found to considerably raise the photothermocatalytic activity of Ni/Mg‐Al2O3 because of the apparent activation energy (Ea) being substantially decreased upon focused illumination. The Ea reduction is associated with the rate‐determining steps of CRM (e.g., CH4 dissociation and the oxidation of carbon species) being accelerated upon focused illumination.

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A unique nanocomposite of Rh quasi-monolayer clusters supported on spinel MgAl2O4 nanosheets with a low Rh loading of 0.15 wt % (Rh/MgAl2O4-MC) was synthesized by a facile method. By the catalyst design, nearly all of Rh atoms are utilized like well-known surface single-atom catalysts. More importantly and surprisingly, Rh/MgAl2O4-MC shows extremely high specific reaction rates of CH4 (r CH4) and CO2 (r CO2) per mole Rh and turnover frequency (TOF) for catalytic CO2 reforming of CH4 (DRM). Its r CH4 and r CO2 are as high as 51.14 and 62.65 mol molRh –1 s–1, which are 4.7 and 4.8 times higher than those of conventional Rh nanoparticles supported on spinel MgAl2O4 nanosheets with a higher Rh loading of 0.96 wt % (Rh/MgAl2O4-NP), respectively. Its TOF values of CH4 and CO2 are as much as 53.9 and 66.1 s–1, which are 3.5 and 3.5 times higher than those of Rh/MgAl2O4-NP, respectively. Meanwhile, Rh/MgAl2O4-MC retains the excellent catalytic durability of supported nanoparticles with negligible side reaction of carbon deposition, which is in striking contrast to the prone deactivation of the single-atom catalysts of precious metals (e.g., Rh and Ru) reported. Experimental evidence and DFT calculations reveal the presence of a strong interaction between Rh quasi-monolayer clusters and MgAl2O4 for Rh/MgAl2O4-MC. The interaction not only makes energetically unstable clusters stable but also alters the reaction pathway of DRM. Compared to DRM on Rh nanoparticles, the oxidations of C* and CH* species as the rate-determining step of DRM are significantly accelerated on Rh quasi-monolayer clusters due to their activation energies being considerably reduced, thus improving intrinsic catalytic activity and inhibiting the side reaction of carbon deposition.

Electric field was not uniformly distributed between RF parallel-plate electrodes in the RF pasteurisation of chili powder. The heating models were reliable to predict experiment results with high precision and accuracy. © 2015 Society of Chemical Industry.

The acetabular cups used in total hip arthroplasty are mostly made of dense metal materials with an elastic moduli much higher than that of human bone. This leads to stress shielding after implantation, which may cause aseptic loosening of the implant. Selective laser melting (SLM) technology allows us to produce tiny and complex porous structures and to reduce the elastic moduli of dense metals, thereby avoiding stress shielding. In the present study, rhombic dodecahedron porous structures with cell sizes of 1 mm, 1.5 mm, and 2 mm were designed. The strut diameter was changed to ensure that the porosity and pore size would meet the bone ingrowth requirements. Then, porous Ti6Al4V alloy specimens were printed using SLM, and compressive tests were carried out. The results showed that the compressive strength and elastic modulus values of the specimens with a cell size of 1.5 mm were in the range of 78.16–242.94 MPa and 1.74–4.17 GPa, respectively, which are in line with the mechanical properties of human cortical bone. Finite element analysis of a total hip joint model was carried out to simulate gait, and the surface of the trabecular acetabular cup was divided into 10 regions according to the stress distribution, with the stress interval in the range of 37.44–219.24 MPa. According to the compression test results, the gradient structure of Ti6Al4V alloy with different porosity was designed for trabecular coating. The gradient porous structure meets the mechanical requirements and is closer to the natural structure of human bone than the uniformly distributed porous structure.