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  4. For the conversion of CO 2 into fuels and chemical feedstocks, hybrid gas/liquid-fed electrochemical flow reactors provide advantages in selectivity and production rates over traditional liquid phase reactors. However, fundamental questions remain about how to optimize conditions to produce desired products. Using an alkaline electrolyte to suppress hydrogen formation and a gas diffusion electrode catalyst composed of copper nanoparticles on carbon nanospikes, we investigate how hydrocarbon product selectivity in the CO 2 reduction reaction in hybrid reactors depends on three experimentally controllable parameters: (1) supply of dry or humidified CO 2 gas, (2) applied potential, and (3) electrolyte temperature. Changing from dry to humidified CO 2 dramatically alters product selectivity from C 2 products ethanol and acetic acid to ethylene and C 1 products formic acid and methane. Water vapor evidently influences product selectivity of reactions that occur on the gas-facing side of the catalyst by adding a source of protons that alters reaction pathways and intermediates. 
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    Free, publicly-accessible full text available June 1, 2024
  5. The growing ubiquity of artificial intelligence (AI) is reshaping much of daily life. This in turn is raising awareness of the need to introduce AI education throughout the K-12 curriculum so that students can better understand and utilize AI. A particularly promising approach for engaging young learners in AI education is game-based learning. In this work, we present our efforts to embed a unit on AI planning within an immersive game-based learning environment for upper elementary students (ages 8 to 11) that utilizes a scaffolding progression based on the Use-Modify-Create framework. Further, we present how the scaffolding progression is being refined based on findings from piloting the game with students. 
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  10. Two-dimensional (2D) atomic layer materials have attracted a great deal of attention due to their superior chemical, physical, and electronic properties, and have demonstrated excellent performance in various applications such as energy storage devices, catalysts, sensors, and transistors. Nevertheless, the cost-effective and large-scale production of high-quality 2D materials is critical for practical applications and progressive development in the industry. Electrochemical exfoliation is a recently introduced technique for the facile, environmentally friendly, fast, large-scale production of 2D materials. In this review, we summarize recent advances in different types of electrochemical exfoliation methods for efficiently preparing 2D materials, along with the characteristics of each method, and then introduce their applications as electrode materials for energy storage devices. Finally, the remaining challenges and prospects for developing the electrochemical exfoliation process of 2D materials for energy storage devices are discussed. 
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