The black-odor water in urban water bodies is increasingly found, resulting in serious atrophy of water bodies and degradation of water ecosystems. At present, the pollution status of the sediments as an internal source still remains much unknown. In order to assess the pollution status of black-odor water sediments, the content of total nitrogen, total phosphorus, organic matter and heavy metals in the sediments were determined by taking the black-odor water sediments in urban areas of Hunan Province as the research object.
View Article and Find Full Text PDFNon-noble transition metal oxides are abundant in nature. However, they are widely regarded as catalytically inert for hydrogen evolution reaction (HER) due to their scarce active electronic states near the Fermi-level. How to largely improve the HER activity of these kinds of materials remains a great challenge.
View Article and Find Full Text PDFThe GF-7 satellite is China's first high-resolution stereo mapping satellite that reaches sub-meter resolution, equipped with new-type payloads, such as an area array footprint camera that can achieve synchronization acquisition of laser spots. When the satellite is in space, the variation of camera parameters may occur due to launch vibration and environmental changes, and on-orbit geometric calibration thereby must be made. Coupled with the data from the GF-7 satellite, this paper constructs a geometric imaging model of the area array footprint camera based on the two-dimensional direction angle, and proposes a coarse-to-fine "LPM-SIFT + Phase correlation" matching strategy for the automatic extraction of calibration control points.
View Article and Find Full Text PDFTransition-metal alloys have attracted a great deal of attention as an alternative to Pt-based catalysts for hydrogen evolution reaction (HER) in alkaline. Herein, a facile and convenient strategy to fabricate CoMo binary alloy nanoparticles nesting onto molybdenum oxide nanosheet arrays on nickel foam is developed. By modulating the annealing time and temperature, the CoMo alloy catalyst displays a superior HER performance.
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