Some Energy Equivalents

Finally, table A1.5 lists the principal physical constants, and table A1.6 presents some energy equivalents of atom units. 

TABLE IV. The Values of Some Energy Equivalents Derived From the Relations E = nu = hcl = hv= kT, and Based on the 2002 CODATA Adjustment of the Values of the Constants... 

Figure 4.1 shows the whole sale prices of a number of possible alternative fuels on an energy equivalent basis compared to conventional gasoline (AlCHE, 1997). Only compressed natural gas (CNG) and liquid petroleum gas (LPG) appear to have some economic advantage relative to gasoline while ethanol, methanol and electricity are at a severe economic disadvantage (Piel, 2001). 

Discussion of Photoelectron and Photofragment Images. The simplest picture for photoexcitation of a molecular Rydberg state would be that of a vertical transition (Av = 0), producing only O2, X(2Ilg)(t = 2) (direct ionization) in the example case. Here electronic motion (ionization) is assumed to be much faster than nuclear motion (dissociation). 02 is much more complicated, of course, and some of the deviations from the simplistic picture could be due not only to the molecule but also to the unconventional three-photon preparation scheme. It is thus important to consider the differences in one-photon and stepwise (2 + 1) excitation. Even with direct one-photon excitation at the energy equivalent of three laser photons, it is known, [78] for example, that the quantum yield for ionization is only 0.5 the other half of the molecules do, in fact, dissociate. 

The roles of NADH and NADPH in the overall strategy of metabolism are shown in Fig. 5.17. Fuel molecules, such as glucose, are oxidised in catabolism they lose electrons and these reducing equivalents are transfered to an environmental acceptor such as oxygen, with concomitant ATP production (see oxidative phosphorylation, Section 5.5.6). However, some reducing equivalents are conserved and re-utilised in the synthesis of cellular components, with the consumption of ATP, as oxidised intermediates are reduced to synthetic precursors with subsequent polymerisation. The pyridine nucleotides thus have roles in both synthetic and energy generation process. 

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