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We develop an adaptive scheme in the kinetic Monte Carlo simulations, where the adsorption and activation energies of all elementary steps, including the effects of other adsorbates, are evaluated "on-the-fly" by employing the neural network potentials. The configurations and energies evaluated during the simulations are stored for reuse when the same configurations are sampled in a later step. The present scheme is applied to hydrogen adsorption and diffusion on the Pd(111) and Pt(111) surfaces and the CO oxidation reaction on the Pt(111) surface. The effects of interactions between adsorbates, i.e., adsorbate–adsorbate lateral interactions, are examined in detail by comparing the simulations without considering lateral interactions. This study demonstrates the importance of lateral interactions in surface diffusion and reactions and the potential of our scheme for applications in a wide variety of heterogeneous catalytic reactions. [ABSTRACT FROM AUTHOR]

Acetic acid fermentation product made from isomalto-oligosaccharide as the main raw material is composed of isomalto-oligosaccharide and acetic acid. In this paper, we have shown that the fermentation product enhanced the expression of disease resistance genes in rice, and that its main functional component was acetic acid. It has been reported so far that acetic acid enhances the jasmonic acid signaling pathway, while the role of isomalto-oligosaccharide in plant defense signaling remains unclear. In this study, we demonstrated the possibility that isomalto-oligosaccharide shifted part of the jasmonic acid signaling pathway, which is enhanced by acetic acid, to the salicylic acid signaling pathway, which is the other major defense pathway. Furthermore, glucose, a constituent monosaccharide of isomalto-oligosaccharide, and a disaccharide maltose had little effect on the signaling pathway, but a trisaccharide maltotriose tended to have a similar effect to isomalto-oligosaccharide on the defense signaling pathway. [ABSTRACT FROM AUTHOR]

The theory of hierarchical equations of motion (HEOM) is one of the standard methods to give exact evaluations of the dynamics as coupled to harmonic oscillator environments. However, the theory is numerically demanding due to its hierarchy, which is the set of auxiliary elements introduced to capture the non-Markovian and non-perturbative effects of environments. When system–bath coupling becomes relatively strong, the required computational resources and precision move beyond the regime that can be currently handled. This article presents a new representation of HEOM theory in which the hierarchy is mapped into a continuous space of a collective bath coordinate and several auxiliary coordinates as the form of the quantum Fokker–Planck equation. This representation gives a rigorous time evolution of the bath coordinate distribution and is more stable and efficient than the original HEOM theory, particularly when there is a strong system–bath coupling. We demonstrate the suitability of this approach to treat vibronic system models coupled to environments. [ABSTRACT FROM AUTHOR]

Erionite (ERI) zeolite has recently attracted considerable attention for its application prospect in the selective catalytic reduction of NOx with NH3 (NH3‐SCR), provided that the high‐silica (Si/Al > 5.5) analog with improved hydrothermal stability can be facilely synthesized. In this work, ERI zeolites with different Si/Al ratios (4.6, 6.4, and 9.1) are synthesized through an ultrafast route, and in particular, a high‐silica ERI zeolite with a Si/Al ratio of 9.1 is obtained by using faujasite (FAU) as a starting material. The solid‐state 29Si MAS NMR spectroscopic study in combination with a computational simulation allows for figuring out the atomic configurations of the Al species in the three ERI zeolites. It is revealed that the ERI zeolite with the highest Si/Al ratio (ERI‐9.1, where the number indicates the Si/Al ratio) exhibits a biased Al occupancy at T1 site, which is possibly due to the presence of a higher fraction of the residual potassium cations in the can cages. In contrast, the Al siting in ERI‐4.6 and ERI‐6.4 proves to be relatively random. [ABSTRACT FROM AUTHOR]

Hexagonal Ag3YCl6 was found to transform into a new phase by applying pressure above ∼1.5 GPa via a diamond anvil cell. In situ XRD analysis revealed that the phase is monoclinic Ag3YCl6. The bulk modulus of the hexagonal and monoclinic phases was 37 GPa and 49 GPa, respectively. Computational investigations also supported this phase transition and bulk modulus. After releasing pressure from 2 GPa, the diffraction peaks of hexagonal Ag3YCl6 were detected, indicating the reversibility of this phase transformation. [ABSTRACT FROM AUTHOR]

The shift of equilibrium by removing water with nitrile dehydrants is crucial for CeO2‐catalyzed synthesis of dialkyl carbonates from CO2 and alcohols. Two nitriles – 2‐cyanopyridine and 2‐furonitrile – were previously found as effective dehydrants, yet their detailed comparison as well as exploration of potential of 2‐furonitrile remain insufficient. Herein, the performance of 2‐cyanopyridine and 2‐furonitrile was compared in the synthesis of various dialkyl carbonates. 2‐furonitrile was found to be superior to 2‐cyanopyridine in the synthesis of dialkyl carbonates from CO2 and bulky or long‐chain (≥C3) alcohols. Namely, the yield of diisopropyl carbonate (up to 50 %) achieved using CeO2 and 2‐furonitrile is comparable to or even higher than previously reported ones. Meanwhile, 2‐cyanopyridine acted as a better dehydrant than 2‐furonitrile in the synthesis of dimethyl carbonate and diethyl carbonate. The adsorption experiments and density functional theory calculations have indicated that the better performance of 2‐furonitrile compared to 2‐cyanopyridine in the synthesis of dialkyl carbonates from bulky or long‐chain alcohols is due to the weaker interaction of 2‐furonitrile with the CeO2 surface. Such weak interaction of 2‐furonitrile offers a larger reaction field on the catalyst surface for both CO2 and alcohols. [ABSTRACT FROM AUTHOR]