Direct Observation of Solvent-Reaction Intermediate Interactions in Heterogeneously Catalyzed Alcohol Coupling.

The relative stability of reactive intermediates and reactants on a surface, which dictates the rate and selectivity of catalytic reactions in both gas and liquid phases, is dependent on numerous factors. One well-established example is secondary interactions, such as van der Waals interactions between the catalyst surface and the pendant group of the intermediate, which can govern reaction selectivity for coupling reactions. Herein, we directly show that interactions between adsorbed reaction intermediates and reactant molecules increase the binding energy and affects the geometrical arrangement of coadsorbed reactant/solvent molecules.

Toward benchmarking theoretical computations of elementary rate constants on catalytic surfaces: formate decomposition on Au and Cu.

With the emergence of methods for computing rate constants for elementary reaction steps of catalytic reactions, benchmarking their accuracy becomes important. The unimolecular dehydrogenation of adsorbed formate on metal surfaces serves as a prototype for comparing experiment and theory. Previously measured pre-exponential factors for CO formation from formate on metal surfaces, including Cu(110), are substantially higher than expected from the often used value of /, or ∼6 × 10 s, suggesting that the entropy of the transition state is higher than that of the adsorbed formate.

Facilitating hydrogen atom migration via a dense phase on palladium islands to a surrounding silver surface.

The migration of species across interfaces can crucially affect the performance of heterogeneous catalysts. A key concept in using bimetallic catalysts for hydrogenation is that the active metal supplies hydrogen atoms to the host metal, where selective hydrogenation can then occur. Herein, we demonstrate that, following dihydrogen dissociation on palladium islands, hydrogen atoms migrate from palladium to silver, to which they are generally less strongly bound.

Quantitative measurement of biotin-binding immunoglobulin G in human sera using F(ab')2 anti-human IgG-coated multi-well plates.

Biotin-binding human immunoglobulin G (B-IgG) was quantitatively measured using an F(ab')2anti-human IgG-coated multi-well microplate for the first time. B-IgG was caught by F(ab')2anti-human IgG and was detected by the following detecting reagents: Peroxidase-labeled streptavidin, avidin and peroxidase-biotin, or avidin-biotinylated peroxidase complex with method A, B, or C, respectively. Commercially available B-IgG was detected by all these three methods.