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Integration of more thermodynamically favorable valorization of biomass (e.g., glycerol), compared to sluggish oxygen evolution, with H2 production is of great significance for energy‐saving electrosynthesis of value‐added chemicals. However, its widespread deployment has been challenged by costly electrocatalysts and large overpotential reaching an industrial‐relevant current density (≥400 mA cm−2). Herein, carbon shell‐encapsulated manganese‐doped cobalt nitride nanoarrays immobilizing on nickel foam, denoted Mn‐CoN@C/NF, are crafted via hydrothermal method and ammoniation. As a bifunctional electrocatalyst, the Mn‐CoN@C/NF manifests extraordinary activity for glycerol oxidation reaction (GOR) with an ultralow potential of 1.37 V (versus RHE) at 400 mA cm−2, in conjunction with H2 evolution reaction (HER) with a low overpotential of 31 mV at 10 mA cm−2. A record high Faradaic efficiency (97.7%) for formate production of GOR is delivered at 1.35 V (vs RHE). Impressively, a two‐electrode electrolyzer capitalizing on the Mn‐CoN@C/NF as catalysts reaches 800 mA cm−2 at 1.83 V, delivering an electricity‐saving efficiency of 15.0% compared to pure water splitting. DFT calculations substantiate that Mn species within Mn‐CoN not only optimize hydrogen adsorption kinetics for HER, but also elevate Co3+ active sites' density for GOR. This work offers an energy‐saving and efficient electrosynthesis avenue for coproduction of valuable chemicals. [ABSTRACT FROM AUTHOR]

In teacher-fronted kindergarten classrooms, questions are an efficient strategy to attract students' attention and guide them through a lesson. However, few studies have examined the related issues by taking co-speech hand gestures into consideration. By annotating and analyzing a videotaped lesson in a Chinese public kindergarten, the present study intends to solve the following problems: (1) What types of questions are posed by the teacher? (2) What types of hand gestures co-occur with these questions and how do gestures contribute to them? (3) What are the patterns of question-initiated sequences and how do the co-occurring hand gestures function? Three types of Mandarin questions ("yes-no" questions, "specific/content" questions and "positive-negative" questions) and a variety of sequence patterns are seen to recur in the selected class. Meanwhile, hand gestures function in multiple ways: (1) signifying, visualizing and reproducing a propositional content (i.e. referential function), and (2) indicating an off-propositional aspect of a question, an answer or a comment (i.e. pragmatic function). This study demonstrates that analyzing extra-speech modes, and especially co-speech hand gestures, is worth both the academic efforts of linguists and practitioners of early childhood education.

The article presents the discussion on correction notice "Teaching and learning pragmatics: Where language and culture meet."