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Herein, we introduce a La 1Àx Sr x CoO 3 perovskite catalyst, substituting for Pt containing LNT catalysts, to remove efficiently NO x from lean-burn engines. The NO x storage/reduction occurred alternatively on the perovskite in successive lean/rich atmospheres, and the NO x conversion reached 71.4% with 100% selectivity to N 2 at 300 C.

Nanocarbon-supported Pt nanoparticles (NPs) were prepared and tested for the propane dehydrogenation reaction (PDH). The nanocarbon support is composed of a nanodiamond core and a defective, ultrathin graphene nanoshell (ND@G). The Pt/ND@G catalyst experienced slight deactivation during the 100 h PDH test, while the Pt/Al 2 O 3 catalyst showed severe deactivation after the 20 h PDH test. Pt NPs exhibited superior sintering resistance versus that of the ND@G support. This particular support structure of ND@G allows electrons on the defects to transfer to the Pt NPs, leading to a strong metal−support interaction, which significantly prevents Pt NP sintering and promotes the desorption of electron-rich propylene. This electron transfer mechanism was also confirmed by a CO catalytic oxidation test.

Oxygen vacancies (OVs) can improve catalytic activities in oxygen evolution reaction (OER). Although considerable effort has been devoted to increasing the OVs concentration in electrocatalysts, limited OVs have been created by current techniques so far. Here, we, for the first time, engineered (i.e., created) abundant OVs into perovskites by element doping and plasma treatment. The results revealed that more OVs were manufactured by combination of Sr doping with Ar plasma treatment, leading to improved OER activity and high stability of LaCoO 3 perovskite. The La 1-x Sr x CoO 3-δ (x = 0.3) sample with Ar plasma treatment (denoted as Sr-0.3-p) showed high OER activity and stability due to the existence of rich OVs, which provided large amounts as well as high intrinsic activity of active sites in OER. The combination of two OV-creating techniques provides an efficient strategy to develop OV-rich catalysts for various applications.

Projecting the distribution of malaria vectors under climate change is essential for planning integrated vector control activities for sustaining elimination and preventing reintroduction of malaria. In China, however, little knowledge exists on the possible effects of climate change on malaria vectors. Here we assess the potential impact of climate change on four dominant malaria vectors (An. dirus, An. minimus, An. lesteri and An. sinensis) using species distribution models for two future decades: the 2030 s and the 2050 s. Simulation-based estimates suggest that the environmentally suitable area (ESA) for An. dirus and An. minimus would increase by an average of 49% and 16%, respectively, under all three scenarios for the 2030 s, but decrease by 11% and 16%, respectively in the 2050 s. By contrast, an increase of 36% and 11%, respectively, in ESA of An. lesteri and An. sinensis, was estimated under medium stabilizing (RCP4.5) and very heavy (RCP8.5) emission scenarios. in the 2050 s. In total, we predict a substantial net increase in the population exposed to the four dominant malaria vectors in the decades of the 2030 s and 2050 s, considering land use changes and urbanization simultaneously. Strategies to achieve and sustain malaria elimination in China will need to account for these potential changes in vector distributions and receptivity.

Mussel-inspired polydopamine catalyst carriers dramatically enhance the catalytic performance (∼450%) of Au nanoparticles in methylene blue reduction, which is attributed to the local enrichment mechanism caused by the favourable attractive interaction between the polydopamine and reactants.