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The effect of traces of ethanol in supercritical carbon dioxide on the mixture's thermodynamic properties is studied by molecular simulations and Taylor dispersion measurements. This mixture is investigated along the isobar p = 10 MPa in the temperature range between T = 304 and 343 K. Along this path, the mixture undergoes two transitions First, the Widom line is crossed, marking the transition from liquid-like to gas-like conditions. A second transition occurs from the supercritical gas-like domain to a subcritical gas. this website The Widom line crossover entails inflection points for most of the studied properties, i.e. density, enthalpy, shear viscosity, Maxwell-Stefan and intradiffusion coefficients. On the other hand, the transition between the super- and subcritical regions is found to be generally smooth, an observation that is qualitatively confirmed by experimental Taylor dispersion measurements. Dedicated atomistic simulations show the presence of microheterogeneities due to ethanol self-association along the investigated path, which lead to the mixture's anomalous behavior in its extended critical region.The hydrogen abstraction (HB) and addition reactions (HD) by H radicals are examined on a series of polycyclic aromatic hydrocarbon (PAH) monomers and models of quasi-surfaces using quasi-classical trajectory (QCT) method. QCT results reproduce the rate constants of HB reactions on PAH monomers from density functional theory (DFT) in the range of 1500-2700 K. The PAH size has a minor impact on the rates of HB reactions, especially at temperatures beyond 2100 K. In contrast, HD reactions have a clear size dependence, and a larger PAH yields a higher rate. It was also found that the preferred reaction pathway changes from HB to HD reactions at ∼1900 K. The rates of surface HB and HD reactions exceed those in the gas phase by nearly one factor of magnitude. Further analysis of the detailed trajectory of the QCT method reveals that about 50% of surface reactions can be attributed to the events of surface diffusion, which depends on the local energy transfer in gas-surface interactions. However, this phenomenon is not preferred in PAH monomers, as expected. Our finding here questions the treatment of the surface reactions of soot as the product of the first collision between the gaseous species and particle surface. The surface diffusion-induced reactions should be accounted for in the rates of the surface HB and HD reactions. The rate constants of HB and HD reactions on each reactive site (surface zig-zag, surface free-edge and pocket free-edge sites) were calculated by QCT method, and are recommended for the further development of surface chemistry models in soot formation.Plasmon-induced hot carriers have recently attracted considerable interest, but the energy efficiency in visible light is often low due to the short lifetime of hot carriers and the limited optical absorption of plasmonic architectures. To increase the generation of hot carriers, we propose to exert multiple plasmonic resonant modes and their strong coupling using a metal-dielectric-metal (MDM) nanocavity that comprises an Au nanohole array (AuNHA), a TiO2 thin film and an Au reflector. Unlike common MDM structures, in addition to the Fabry-Pérot mode in the dielectric layer, AuNHA as the top layer is special because it excites the localized surface plasmon resonance (LSPR) mode in the Au nanoholes and launches the gap surface plasmon polariton (GSPP) mode in the Au reflector surface. The spatial field overlapping of the three resonance modes enables strong mode coupling by optimizing the TiO2 thickness, which leads to notably enhanced average IPCE (∼1.5%) and broadband photocurrent (170 μA·cm-2). This MDM structure would be useful for photochemistry and photovoltaics using sunlight.Herein, we report a general strategy based on host-guest interactions to fabricate atomically dispersed biomimetic catalysts, which were evaluated by diboration of phenylacetylene. The structure and function of these mimics are quite similar to those of enzymes, namely, the atomically dispersed metal serves as an active site, the external macromolecular structure plays a role as an enzyme catalytic pocket to stabilize the reaction intermediates and the interactions between the intermediates and functional groups near to the active site can reduce the reaction activation energy.Galvanic replacement reactions are a reliable method for transforming monometallic nanotemplates into bimetallic products with complex nanoscale architectures. When replacing bimetallic nanotemplates, even more complex multimetallic products can be made, with final nanocrystal shapes and architectures depending on multiple processes, including Ostwald ripening and the Kirkendall effect. Galvanic replacement, therefore, is a promising tool in increasing the architectural complexity of multimetallic templates, especially if we can identify and control the relevant processes in a given system and apply them more broadly. Here, we study the transformation of intermetallic PdCu nanoparticles in the presence of HAuCl4 and H2PtCl6, both of which are capable of oxidizing both Pd and Cu. Replacement products consistently lost Cu more quickly than Pd, preserved the crystal structure of the original intermetallic template, and grew a new phase on the sacrificial template. In this way, atomic and nanometer-scale architectures are integrated within individual nanocrystals. Product morphologies included faceting of the original spherical particles as well as formation of core@shell and Janus-style particles. These variations are rationalized in terms of differing diffusion behaviors. Overall, galvanic replacement of multimetallic templates is shown to be a route toward increasingly exotic particle architectures with control exerted on both Angstrom and nanometer-scale features, while inviting further consideration of template and oxidant choices.Very recently, directing group (DG) migration has emerged as a practical strategy for transition-metal-catalysed direct C-H activation, resulting in a highly atom-economical process and enabling the reusage of DG. Therefore, great progress has been made in developing multitasking DGs. In this tutorial review, we present the rapid advances of this novel strategy by analyzing and comparing the different types of migratable DGs (including N-O, N-C, N-N or O-C bond cleavage to trigger DG migration). The related mechanisms, as well as synthetic applications, are also mentioned.