Most processes for recovering zinc from electric arc furnace (EAF) dust employ carbon as a reducing agent for zinc oxide in the dust. In the present work, the reduction reaction of zinc oxide with carbon in the presence of various additives was kinetically studied. The effects of temperature and the additives of Fe 2 O 3 , mill scale, and CaCO 3 on the kinetics of the reduction reaction were measured in the temperature range of 1173-1373 K under nitrogen atmosphere. The mill scale is one of byproducts generated from the steel rolling process. It was found from the experimental results that all three additives enhance the reaction rate of zinc oxide with carbon, but the effect of CaCO 3 addition is the highest. The increase in the reaction rate is because Fe 2 O 3 , mill scale, and CaCO 3 in the reduction reaction promote the carbon gasification reaction. The spherical shrinking core model for a surface chemical reaction control was also found to be useful in describing the kinetics of the reaction, which had an activation energy of 224 kJ/mol (53 kcal/mol) for ZnO-C reaction system, 175 kJ/mol (42 kcal/mol) for ZnO-Fe 2 O 3 -C reaction system, 184 kJ/mol (44 kcal/mol) for ZnO-mill scale-C reaction system, and 161 kJ/mol (39 kcal/mol) for ZnO-CaCO 3 -C reaction system.

The quantification of supramolecular host–guest interactions is important for finely modulating supramolecular systems. Previously, most host–guest interactions quantified using force spectroscopic techniques have been reported in force units. However, accurately evaluating the adhesion energies of host–guest pairs remains challenging. Herein, using a surface forces apparatus, we directly quantify the interaction energies between cyclodextrin (CD)-modified surfaces and ditopic adamantane (DAd) molecules in water as a function of the DAd concentration and the CD cavity size. The adhesion energy of the β-CD–DAd complex drastically increased with increasing DAd concentration and reached saturation. Moreover, the molecular adhesion energy of a single host–guest inclusion complex was evaluated to be ~9.51 kBT. This approach has potential for quantifying fundamental information toward furthering the understanding of supramolecular chemistry and its applications, such as molecular actuators, underwater adhesives, and biosensors, which require precise tuning of specific host–guest interactions.

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In the era of the Internet of Things, digital displays play a critical role in human-machine interfaces. In particular, displays applied to contemporary devices such as flexible smart watches and foldable/rollable electronics underline the need for pertinent materials and device technologies to fulfill their designed functions. However, despite the technical advancements of electronic components such as stretchable/flexible electrodes and flexible backplanes, their proper assembly remains a challenge. Herein, we report the compositional effect of acrylic acid (AA) on the physical properties of as-synthesized pressure sensitive adhesives (PSAs), especially on their adhesion performance in terms of wettability and peel adhesion. Accordingly, an empirical criterion for intimate wetting is proposed based on the storage modulus of the PSAs. In this study, the PSA with the best adhesion performance was evaluated for its viscoelastic properties and suitability for specific applications. The results demonstrated the strain-dependent conformational recovery of the adhesive; the implementation of the prestrain strategy enables rapid strain reversibility at 25% of the total strain. Furthermore, the AA-incorporated PSAs exhibited remarkable metal corrosion resistance as well as high optical clarity. Thus, this fundamental study of stretchable PSAs can provide useful guidance for the development of advanced PSAs that can be used in a wide range of applications involving display devices.

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