Decoherence of a shallow donor electron spin in silicon caused by electron-lattice interaction is studied. We find that there are two time scales associated with the evolution of the electron spin density matrix: the fast but incomplete decay due to the interaction with non-resonant phonons followed by slow relaxation resulting from spin flips accompanied by resonant phonon emission. We estimat...

Several strains of Gram-negative and Gram-positive sulphate-reducing bacteria (SRB) are able to use carbon monoxide (CO) as a carbon source and electron donor for biological sulphate reduction. These strains exhibit variable resistance to CO toxicity. The most resistant SRB can grow and use CO as an electron donor at concentrations up to 100%, whereas others are already severely inhibited at CO...

The effect of donor-like surface traps on two-dimensional electron gas (2DEG) and drain current collapse of AlGaN/GaN high electron mobility transistors (HEMTs) has been investigated in detail. The depletion of 2DEG by the donor-like surface states is shown. The drain current collapse is found to be more sensitive to the addition of positive surface charges. Surface trap states with higher ener...

1. A spectrophotometric assay is described that enables the hydroxylation of p-coumaric acid to caffeic acid, catalysed by spinach-beet phenolase, to be followed continuously. 2. Initial-velocity and inhibitor studies indicate that the order of substrate addition is oxygen, p-coumaric acid and electron donor, with an irreversible step separating the binding of each substrate. 3. Caffeic acid is...

A donor–acceptor linked triad with a short spacer (Fc-ZnP-C60) 1 was designed and synthesised to attain the longest charge-separation lifetime, 630 ms, ever reported for triads at room temperature. The ferrocene electron donor and fullerene electron acceptor of triad 1 are attached to imidazole rings fused to opposite b,b0-pyrrolic positions of the zinc porphyrin. After excitation of the porphy...

Neutral organic electron donors, featuring pyridinylidene-imidazolylidene, pyridinylidene-benzimidazolylidene and imidazolylidene-benzimidazolylidene linkages are reported. The pyridinylidene-benzimidazolylidene and imidazolylidene-benzimidazolylidene hybrid systems were designed to be the first super electron donors to convert iodoarenes to aryl radicals at room temperature, and indeed both sh...

Organic photovoltaic cell (OPV) has emerged as a new competitor to inorganic material-based solar cells, due to its potential application in large area, printable, and flexible solar panels. In particular, OPV cells with bulk heterojunction architecture (BHJ), in which the photoactive layer consists of a bicontinuous blend of an electron donor and an electron acceptor, has allowed power convers...

Electron-transfer rate constants were measured for a variety of molecular systems. The rate constant was found to depend upon the nature of the medium between the electron donor and acceptor moieties. Using a superexchange model to calculate the electronic coupling between donor and acceptor, the effect of orbital energetics was studied. For photoinduced electron transfer, aromatic moieties wit...

Silver nanoparticles are increasingly used in various fields of biotechnology and applications in the medicine. Objectives of this study were optimization of production of silver nanoparticles using biotransformations by Fusarium oxysporum, and a further study on the location of nanoparticles synthesis in this microorganism. The reaction mixture contained the following ingredients (final concen...

Visible light-induced charge transfer dynamics were investigated in a novel transition metal triad acceptor-chromophore-donor, (NDI-phen)Pt(II)(-C≡C-Ph-CH2-PTZ)2 (1), designed for photoinduced charge separation using a combination of time-resolved infrared (TRIR) and femtosecond electronic transient absorption (TA) spectroscopy. In 1, the electron acceptor is 1,4,5,8-naphthalene diimide (NDI), ...