The catalytic cycle of numerous enzymes involves the coupling between proton transfer and electron transfer. Yet, the understanding of this coordinated transfer in biological systems remains limited, likely because its characterization relies on the controlled but experimentally challenging modifications of the free energy changes associated with either the electron or proton transfer. We have ...

A phosgene-free synthesis of symmetrical N,N'-disubstituted urea by the reaction of aromatic and aliphatic primary amines and urea promoted by  microwave irradiation in the presence of a suitable energy-transfer solvent such as N-N-dimethylacetamide is described.

We develop a model of electron transfer reactions at conditions of nonergodicity when the time of solvent relaxation crosses the observation time window set up by the reaction rate. Solvent reorganization energy of intramolecular electron transfer in a charge-transfer molecule dissolved in water and acetonitrile is studied by molecular dynamics simulations at varying temperatures. We observe a ...

zns  nanoparticles  were  synthesized  via  a  simple  surfactant  free microwave  route.  in  this  synthesis, thioacetamide  was  used  as sulfur  source.  the effects  of different  parameters  such  as  type of zinc precursor,  time  and  power  of  irradiation  on  the  morphology and  particle  size  of  the  products  have been  investigated.  the nanostructures  were  characterized  by ...

introduction: the aim of this study was to investigate the scanning electron microscope (sem) analysis of tooth surface irradiated by different parameters of er:yag laser. methods: 15 caries-free extracted human third molars were used in this study. the teeth were put into 5 groups for laser irradiation as follows: group 1 (power: 2.5 w, energy: 250 mj); group 2(power: 3 w, energy: 300 mj); gro...

Using molecular dynamics simulations of the thermodynamic integration type, we study the energetics and kinetics of electron transfer through the nitrite reductase enzyme of Sulfurospirillum deleyianum, Wolinella succinogenes and Campylobacter jejuni. In all of these five-heme proteins, the storage of an even number of electrons within a monomeric chain is thermodynamically favoured. Kineticall...

Two classes of fullerene-based donor-bridge-acceptor (D-B-A) systems containing donors of varying oxidation potentials have been synthesized. These systems include fullerenes linked to heteroaromatic donor groups (phenothiazine/phenoxazine) as well as substituted anilines (p-anisidine/p-toluidine). In contrast to the model compound, an efficient intramolecular electron transfer is observed from...