core-shelled Ni/NiO nanowires via an N 2 H 4 ⋅H 2 O reduction method for microstructure and magnetic property investigations. [17] In addition, some carbon modified NiO/Ni materials were also prepared. [8-11,19,20] Chinnappan et al. synthesized C@NiO/Ni nanofibers via an electrospinning method for hydrogen evolution reaction. [11] Lv et al. prepared a series of MOF-derived NiO/Ni@C magnetic composites with chestnut shelllike hollow sphere structure for arsenic removal. [15] Nevertheless, it can be found that many methods are complicated, highcost, harm to the environment, thereby limiting their large-scale production and application. Currently, biomass template-assisted method has attracted extensive attention of researchers because it endows materials with diverse morphologies and improved performances. There are many biomass templates used, such as eggshell membrane, [12] ginkgo leaves, [22] chicken feathers, [23] cotton fibers, [24] pomelo-orange peels, [25,26] etc. Among them, cotton fiber (CF) consisting of cellulose and hemicellulose and pectin, contains abundant polar/active groups including-OH,-NH, and-C-O/N-C (seen in Figure S1, Supporting Information), making it well H 2 O-wet, swell, easily removed under air atmosphere. Thus, it is used as a vital template to give as-obtained material fibrous morphology and improved property. Herein, two series of hollow fibered Ni/NiO@C composites were successfully fabricated via a novel template-assisted dipping/adsorbing and calcining method by using CF as a multifunctional template and Ni(NO 3) 2 •6H 2 O as Ni source without any other additives, such as reducer, alkali agents, and extra carbon (C) source (Figure 1). During the preparation process, Ni 2+ ions were firstly adsorbed on the surface of wetting and swelling CFs to produce the precursors (Ni 2+ /CF), and then the precursors were calcined under an air condition to obtain target Ni/NiO@C material. It is worth pointing out that the asprepared materials show good magnetic, adsorptive, and electrolysis properties. 2. Results and Discussion 2.1. SEM and TEM Analyses Considering ST-200 sample delivered the best magnetic, adsorptive, and electrocatalytic properties, we thus take it as a Two series of hierarchically Ni/NiO@C hollow-fibers with magnetic, adsorptive, and electrocatalytic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) properties are successfully prepared via a facile and green cotton fiber (CF)-templated dipping/adsorbing-calcining strategy. The effect of calcination temperature and CF amount on morphologies, components, and properties of the as-prepared materials is investigated. The results demonstrate that a proper CF template can endow the as-obtained materials with hierarchically hollow-fiber morphology and multi-components (Ni 0 , NiO, and C) at a certain calcination temperature, therefore providing excellent magnetic, adsorptive, and electrocatalytic OER and HER properties. Specifically, the unique hierarchical morphology and synergistic effect between Ni 0 and NiO remar...

Rational design of active and earth-abundant catalysts toward oxygen evolution reaction (OER) is of particular significance for archiving highly efficient water electrolysis. Herein, a series of perovskite oxide quantum dots with abundant oxygen vacancies adhered on oxidized carbon nanotubes (LaNi X Fe 1-X O 3-δ -QDs/ CNTs) were fabricated by simple sol-gel and pyrolysis methods. The results indicate that the optimized LaNi 0.3 Fe 0.7 O 2.759 -QDs/ CNTs sample with adjust crystal structure, proper ratio of Ni to Fe, and desirable oxygen vacancy concentration shows a low overpotential (0.34 V at 10 mA/cm 2 ), a low Tafel slope (74 mV dec À 1 ), and excellent stability when it was evaluated as OER electrocatalyst. This work will shed light on the development of precious-metal-free catalysts with promoted catalytic performance [a

Developing durable and highly active non-noble electrocatalysts for oxygen evolution reaction (OER) is highly desirable for water splitting. Herein, we report a NiFe carbonate hydroxides embedded in a carbon nanotubes and graphite composite material (NiFe CHs-CNT/G) by a facile and green precipitation method. The NiFe CHs are in-situ grown on CNT/G using NH 3. H 2 O as precipitant and CO 2 in air as the source of CO 3 2À under room temperature and pressure. The introduction of CNT/G not only improves the conductivity of material, but also enhances the combination of CNT/G and NiFe CHs nanosheets, thereby accelerating the transfer of electrons and reactants. Meanwhile, the catalyst with a special sandwich morphology provides larger active area to expose more active sites. Moreover, the effective interaction within the Ni and Fe in NiFe CHs-CNT/G is benefiting for improving OER performance. All these lead to the optimized NiFe CHs-CNT/G catalyst delivers an outstanding OER performance with a low overpotential of 300 mV at 10 mA cm À 2 and a small Tafel slope of 60.13 mV dec À 1 .

In view of the current higher requirements for comfort issues such as adaptive car seat adjustment, human size measurement technology is gradually improving in China. In this paper, combined with the non-contact measurement technology method, a body size measurement system based on image processing is proposed. It combines image processing methods such as open pose human pose estimation and edge detection, and achieves the advantages of simple algorithm, fast processing speed and high accuracy, the error rate is 0.19125, to prepare for the self-adaptive car seat adjustment system, and also to provide a reliable reference for further improving the measurement method of human body size.

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