Developing bi-functional electrocatalysts for both oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is crucial for enhancing the energy transfer efficiency of metal-air batteries and fuel cells, as well as producing hydrogen with a high purity. Herein, a series of Pd-Ru alloyed nanoparticles encapsulated in porous carbon nanosheets (CNs) were synthesized and employed as a bifunctional electrocatalyst for both ORR and HER. The TEM measurements showed that Pd-Ru nanoparticles, with a size of approximately 1-5 nm, were uniformly dispersed on the carbon nanosheets. The crystal and electronic structures of the Pd x Ru 100−x /CNs series were revealed by powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The as-prepared samples exhibited effective ORR activity in alkaline media and excellent HER activity in both alkaline and acid solutions. The Pd 50 Ru 50 /CNs sample displayed the best activity and stability among the series, which is comparable and superior to that of commercial 10% Pd/C. For ORR, the Pd 50 Ru 50 /CNs catalyst exhibited an onset potential of 0.903 V vs. RHE (Reversible Hydrogen Electrode) and 11.4% decrease of the current density after 30,000 s of continuous operation in stability test. For HER, the Pd 50 Ru 50 /CNs catalyst displayed an overpotential of 37.3 mV and 45.1 mV at 10 mA cm −2 in 0.1 M KOH and 0.5 M H 2 SO 4 , respectively. The strategy for encapsulating bimetallic alloys within porous carbon materials is promising for fabricating sustainable energy toward electrocatalysts with multiple electrocatalytic activities for energy related applications.

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<p>The inaccuracy of acute altitude sickness screening has brought great challenges to power grid construction workers in high–altitude areas. Human vital signs monitoring technology is an effective technical means to prevent people from developing altitude sickness. This paper proposes a monitoring and evaluation platform for high altitude sickness in power grid operations based on information entropy of the causes of the illness. First, the vital characteristics data of workers are collected through sensors such as blood pressure and blood oxygen. Secondly, the collected data is transmitted back to the platform by using the Internet of Things technology. The information entropy establishes an analysis model of altitude sickness and generates personnel evaluation reports and treatment recommendations. Finally, the application results of the platform verified that the preventive effect of the platform is much higher than that of the pre–existing physical examination method.</p>