A MODEL OF THE LINEAR HYDROGEN BOND HAS BEEN DEVISED WHICH IS CHARACTERIZED BY THREE PHYSICAL PARAMETERS OF THE ISOLATED ELECTRON DONOR AND PROTON DONOR MOLECULES: mu(A-H), the bond dipole moment; DeltaI, the difference in ionization potential between that of the electron donor and the corresponding noble gas atom; and l, the length of the electron donor lone-pair of electrons. The model is abl...

In this chapter the fundamental aspects involved in biological treatment processes applied for the removal of nitrogen from wastewaters are described. A comprehensive review of the literature is provided including kinetic, microbiological and biochemical aspects of nitrification, denitrification and anammox, as well as key operational parameters affecting the processes. This information is rele...

Photochemical electron transfer reactions on a picosecond time scale have been studied in two covalently-linked donor-acceptor systems. The first molecule is a chlorophyll-porphyrin-quinone triad that closely mimics photosynthetic charge separation by undergoing picosecond electron transfer in low temperature glasses to yield a radical ion pair that lives for 2 ms and exhibits spin-polarization...

We report a general strategy for fine-tuning the bandgap of donor-acceptor-donor based organic molecules by modulating the electron-donating ability of the donor moiety by changing the benzochalcogenophene donor groups from benzothiophenes to benzoselenophenes to benzotellurophenes. These molecules show red-shifts in absorption and external quantum efficiency maxima from sulfur to selenium to t...

The origin of high background electron concentration (n) in InxGa1−xN alloys has been investigated. A shallow donor was identified as having an energy level (ED1) that decreases with x (ED1 = 16 meV at x = 0 and ED1 = 0 eV at x ∼ 0.5) and that crossover the conduction band at x ∼ 0.5. This shallow donor is believed to be the most probable cause of high n in InGaN. This understanding is consiste...