This study examined how instructional design (ID) experts used their prior knowledge and previous experiences to solve an ill‐structured instructional design problem. Seven experienced designers used a think‐aloud procedure to articulate their problem‐solving processes while reading a case narrative. Results, presented in the form of four assertions, showed that experts (1) narrowed the problem space by identifying key design challenges, (2) used an amalgam of knowledge and experience to interpret the problem situation, (3) incorporated a mental model of the ID process in their problem analyses, and (4) came to similar conclusions about how to respond to the situation, despite differences in their initial conceptualizations. Implications for educating novice instructional designers are discussed.
Zinc–air batteries (ZABs) are promising as energy storage devices owing to their high energy density and the safety of electrolytes. Construction of abundant triple‐phase boundary (TPB) effectively facilitates cathode reactions occurring at TPB. Herein, a wood‐derived integral air electrode containing Co/CoO nanoparticles and nitrogen‐doped carbonized wood (Co/CoO@NWC) is constructed with a dual catalytic function. The potential gap between oxygen reduction and evolution is shortened to 0.77 V. Liquid ZABs using Co/CoO@NWC as cathode exhibit high discharge specific capacity (800 mAh gZn−1), low charge–discharge gap (0.84 V), and long‐term cycling stability (270 h). Co/CoO@NWC also shows distinguished catalytic activity and stability in all‐solid‐state ZABs. The inherent layered porous and pipe structures of wood are well maintained in catalytically active carbon. The different hydrophilicity of carbonized wood and Co/CoO endow abundant TPBs for battery reaction. The Co/CoO located on TPB provides main active sites for oxygen reactions. The inherent pipe structures of wood carbon and the interaction between Co/CoO and NWC effectively prevent nanoparticles from aggregation. The design and preparation of this monolithic electrocatalyst contribute to the broad‐scale application of ZABs and promote the development of next‐generation biomass‐based storage devices.
In this article, Co-based metal organic frameworks (MOFs) with two shapes were used as pyrolysis precursor to synthesize multilayer core-shells composites loaded on reduced graphene oxide (rGO) sheets. The core-shell structures were obtained by the formation of cores from metal ions and carbon shells from carbonization of ligands. Controllable oxidation of Co cores to CoOx shells generated multilayer core-shell structures anchored onto the surface of rGO sheets. The N-doped composites were obtained by adding poly vinylpyrrolidone. The multilayer core-shells composites exhibited superior catalytic activity toward hydrogen generation compared to their single layer counterparts. By using the N-doped multilayer composites, high hydrogen generation specific rate of 5560 mL min(-1) gCo(-1) was achieved at room temperature. The rGO sheets in composites improved their structure stability. These catalysts exhibited high stability after used five cycling. This synergistic strategy proposes simple, efficient, and versatile blue-prints for the fabrication of rGO composites from MOFs-based precursors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.