A Research on the Application of the“Internet Plus Swimming”Teaching Mode in Universities

This study focuses on the reform and development of physical education in colleges and universities in the post-epidemic era,beginning from the design of an innovative“Internet Plus Swimming”teaching mode to enhance the quality of swimming lessons in colleges and universities,and subsequently applying it to the teaching of technical movements in swimming,so as to promote the teaching reform of swimming lessons in colleges and universities,as well as improve the teaching quality.This study showed that the students in the experimental group were better than those in the control group in four aspects:theoretical knowledge of swimming,speed,technique,and students’independent learning ability.It can be concluded that it is both,effective and feasible to integrate multimedia learning resources,using digital information technology and network mobile devices,to construct the“Internet Plus Swimming”teaching mode and apply it to general swimming courses in colleges and universities in the post-epidemic era.

Enriched electrophilic oxygen species facilitate acidic oxygen evolution on Ru-Mo binary oxide catalysts

The polymer electrolyte membrane(PEM)electrolyzers are burdened with costly iridium(Ir)-based catalysts and high operation overpotentials for the oxygen evolution reaction(OER).The development of earth-abundant,highly active,and durable electrocatalysts to replace Ir is a critical step in reducing the cost of green hydrogen production.Here we develop a Ru5Mo4Ox binary oxide catalyst that exhibits high activity and stability in acidic OER.The electron-withdrawing property of Mo enriches the electrophilic surface oxygen species,which promotes acidic OER to proceed via the adsorbate evolution pathway.As a result,we achieve a 189 mV overpotential at 10 mA·cm^(-2) and a Tafel slope of 48.8 mV·dec^(-1).Our catalyst demonstrates a substantial 18-fold increase in intrinsic activity,as evaluated by turnover frequency,compared to commercially available RuO_(2) and IrO_(2) catalysts.Moreover,we report a stable OER operation at 10 mA·cm^(-2) for 100 h with a low degradation rate of 2.05 mV·h^(-1).

氮调控正价态铜用于高效电化学还原一氧化碳制备乙酸

利用间歇性可再生能源电转化二氧化碳和一氧化碳制备多碳工业原料和燃料能够完善碳循环.然而,二氧化碳转化为乙酸的法拉第效率难以满足大规模应用的要求.研究发现,调控铜的局域电子结构至正价态,以及使用一氧化碳作为反应气均能够提高多碳产物的选择性.因此,我们提出杂原子调控策略,用于调节催化剂表面活性位点的氧化态.密度泛函理论研究表明,掺杂氮原子调控正价态铜位点,在热力学上有利于形成中间体*CCO,进而生成乙酸.我们进一步利用溶剂热法合成氮掺杂的铜催化剂,并通过软X射线吸收谱和X射线光电子能谱证实催化剂表面存在大量正价态铜位点.同时,该催化剂在一氧化碳还原反应中实现了42%的乙酸法拉第效率和已知最高的乙酸偏电流密度180 mA cm^-2.

Flexible sensors based on assembled carbon nanotubes

Flexible sensors have attracted significant attention as they could be directly attached to/implanted into the body or incorporated into textiles to monitor human activities and give feedbacks for healthcare.A typical fabrication method is the direct use of intrinsically flexible active materials such as carbon nanotubes(CNTs).CNTs are generally assembled into aligned structures to extend their remarkable chemical,mechanical,and electrical properties to macroscopic scale to afford high sensing performances.In this review,we present the recent advance of CNT assemblies as electrodes or functional materials for flexible sensors.The realizations of aligned CNTs are firstly investigated.A variety of flexible sensors based on the aligned CNTs are then carefully explored,with an emphasis on understanding the working mechanism for their high sensing properties.The main attention is later paid to comparing two main categories of flexible sensors with fiber and film shapes.The remaining challenges are finally highlighted to offer some insights for future study.