Heavy-enzyme isotope effects (15N-, 13C-, and 2H-labeled protein) explore mass-dependent vibrational modes linked to catalysis. Transition path-sampling (TPS) calculations have predicted femtosecond dynamic coupling at the catalytic site of human purine nucleoside phosphorylase (PNP). Coupling is observed in heavy PNPs, where slowed barrier crossing caused a normal heavy-enzyme isotope effect (...

High-concentration CaO particles and gas compositions have a significant influence on NOx reduction by selective non-catalytic reduction (SNCR) in cement precalciners. The effect of gas composition on NOx reduction by SNCR with NH₃ was studied in a cement precalciner atmosphere with and without CaO at 700-1100 °C. It was found that CaO significantly lowers NOx reduction efficiency between 750 °...

Using first-principles calculations, we model the chemical vapor deposition (CVD) growth of carbon nanotubes (CNT) on nanoparticles of late-transition (Ni, Pd, Pt) and coinage (Cu, Ag, Au) metals. The process is analyzed in terms of the binding of mono- and diatomic carbon species, their diffusion pathways, and the stability of the growing CNT. We find that the diffusion pathways can be control...

In this work, we present a mild method for direct conversion of primary alcohols into carboxylic acids with the use of water as an oxygen source. Applying a ruthenium dihydrogen based dehydrogenation catalyst for this cause, we investigated the effect of water on the catalytic dehydrogenation process of alcohols. Using 1 mol% of the catalyst we report up to high yields. Moreover, we isolated ke...

2 Introduction 3 Results and Discussion 17 A Chromium Diphosphine System for Selective and Catalytic Ethylene Oligomerization 17 Synthesis of PNP Ligands with Ether Groups Tethered to Nitrogen 17 Preparation and Characterization of PNP Chromium Complexes 18 Catalytic Runs at 1 atm of Ethylene Using Precatalysts 21-24 24 Catalytic Runs at Higher Pressures of Ethylene 28 Role of the Ether Tether ...

The effect of storage on the catalytic concentration of cholinesterase and on the reference values of cholinesterase in human serum were studied. When serum was stored at room temperature (20 degrees C), at 4 degrees C and at - 20 degrees C (one year) there was no change in catalytic activity. Even after nine times freezing and thawing (over nine weeks) the catalytic activity was unaffected. Th...

A Sb/palygorskite (PAL) composite was synthesized by a facile solvothermal process and applied in catalytic hydrogenation of p-nitrophenol for the first time. It was found that the Sb nanoparticles with the sizes of 2-5 nm were well dispersed on the fiber of PAL, while partial aggregated Sb nanoparticles with sizes smaller than 200 nm were also loaded on the PAL. The Sb/PAL composite with 9.7% ...

Dopamine, acting via cyclic adenosine 3':5'-monophosphate (cAMP), has been shown to enhance a kainate-gated ionic conductance in white perch retinal horizontal cells in vitro. To determine whether this effect involves stimulation of a protein kinase, kainate-gated currents were observed in cultured horizontal cells that were dialyzed with the catalytic subunit of cAMP-dependent protein kinase. ...

Rh(I) complexes of S-triazines were found very efficient towards the catalytic hydrogenation of alkenes, alkynes at normal pressure and at room temperature. Reduction of aromatic nitrocompounds, benzaldehyde and benzil were observed in appreciable amount only at high pressure and at high temperature. No diminished catalytic activity was observed even after 6-8 repeated catalytic runs. Profound ...

The catalytic pyrolysis of Laminaria japonica was carried out over a hierarchical meso-MFI zeolite (Meso-MFI) and nanoporous Al-MCM-48 using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The effect of the catalyst type on the product distribution and chemical composition of the bio-oil was examined using Py-GC/MS. The Meso-MFI exhibited a higher activity in deoxygenation and aromat...