The hydride growth on metallic surface can cause material failure, which is a significant form of pitting corrosion. A new multiphase-field model constructed to study the corrosion kinetics, in three order parameters are introduced represent passive film, and metal phase, respectively. Coupling with hydrogen concentration field elastic strain field, this not only presents rupture but also revea...

Ruthenium aqua complexes [(eta(6)-C(6)Me(6))Ru(II)(L)(OH(2))](2+) {L = bpy (1) and 4,4'-OMe-bpy (2), bpy = 2,2'-bipyridine, 4,4'-OMe-bpy = 4,4'-dimethoxy-2,2'-bipyridine} and iridium aqua complexes [Cp*Ir(III)(L)(OH(2))](2+) {Cp* = eta(5)-C(5)Me(5), L = bpy (5) and 4,4'-OMe-bpy (6)} act as catalysts for hydrogenation of CO(2) into HCOOH at pH 3.0 in H(2)O. The active hydride catalysts cannot be...

The role of protein flexibility in enzyme-catalyzed activation of chemical bonds is an evolving perspective in enzymology. Here we examine the role of protein motions in the hydride transfer reaction catalyzed by thymidylate synthase (TSase). Being remote from the chemical reaction site, the Y209W mutation of Escherichia coli TSase significantly reduces the protein activity, despite the remar...

The relative (to BEt3) hydride ion affinity (HIA) of a series of acridine borenium salts has been calculated, with some HIAs found to be similar to that for [Ph3C]+. The HIA at the acridine C9 position is controlled by both acridine and the boron substituents, the latter presumably affecting the strength of the B=N bond in the acridane-BY2 products from hydride transfer. Through a range of hydr...

The reaction catalyzed by Escherichia coli dihydrofolate reductase (ecDHFR) has become a model for understanding enzyme catalysis, and yet several details of its mechanism are still unresolved. Specifically, the mechanism of the chemical step, the hydride transfer reaction, is not fully resolved. We found, unexpectedly, the presence of two reactive ternary complexes [enzyme:NADPH:7,8-dihydrofol...

Anion photoelectron spectroscopy and density functional theory were employed to study aluminum hydride clusters, AlnHm (4 e n e 8, 0 e m e 10). Photoelectron spectra revealed that Al4H4, Al4H6, and a family of species with general formula AlnHn+2 (5 e n e 8) have small adiabatic electron affinities and large HOMO-LUMO gaps (ranging from 0.5 to 1.9 eV) relative to those of their stoichiometric n...

Choline oxidase catalyzes the two-step oxidation of choline to glycine betaine, one of limited osmoprotectants, with the formation of betaine aldehyde as an enzyme bound intermediate. Glycine betaine accumulates in the cytoplasm of plants and bacteria as a defensive mechanism to withstand hyperosmolarity and elevated temperatures. This makes the genetic engineering of relevant plants which lack...