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Summary Thermodynamic equilibrium constant method and mathematical model are used to analyze the investigating effects of temperature, α[oxygen‐methane molar ratio] and β [carbon dioxide‐methane molar ratio] on characteristics of oxidative CO2 reforming of methane reaction over Ni/Al2O3 catalysts to produce hydrogen in the membrane reactor. While keeping temperature at 1100 K, the membrane reactor is no longer useful to separate hydrogen when α > 0.6 for hydrogen in reaction side is no longer to permeate side. When increasing β, the methane conversion goes up firstly until the β is 1.3, which is higher than the inflection point at 1.1 in the model prediction. The hydrogen yield peaks at β = 0.5 in permeate side. Increasing the temperature or reducing the β will cause the molar ratio of H2/CO increase. However, changing α has no significant effect on adjusting the molar ratio of H2/CO. By establishing equilibrium reaction model, the system performance can be accurately predicted. Copyright © 2016 John Wiley & Sons, Ltd.

A smart fractal microchannel heat sink (SFMHS) integrated with thermoresponsive hydrogels is developed for the randomly distributed hotspots sensing and adaptive cooling of microelectronic devices. The equally distributed thermo-responsive hydrogels can firstly sense the temperature rise caused by random hotspots and then work as microfluidic valves to reallocate the coolant by its adaptive thermo-shrinkage. The CFD numerical results show that the proposed SFMHS presents lower and more uniform temperature distribution than FMHS under hotspots conditions. The maximum temperature rise, heat source temperature difference, and heat source temperature SD of SFMHS are 4.47, 4.28, and 0.97 K lower than FMHS at the HSB heat flux of 400 W/cm 2 , respectively. The adaptive cooling superiority of SFMHS gets enhanced with the increase of the hotspots area and heat flux density because more hydrogels shrink, and more flow gets reallocated for hotspot-targeted cooling. However, too low (HSA,400 W/cm 2 ) or too high (HSC, 300 W/cm 2 ) hotspots conditions would result in the worse hotspot cooling of SFMHS with no adaptive flow reallocation because all hydrogels are at the same initial or shrunken sates. Meanwhile, SFMHS is more effective to sense and cooling the hotspots that are closer to hydrogels.