Energy budget/balance

The energy released by nuclear reactions provides the power that causes stars, including our Sun, to shine. The realization that stars are fueled by nuclear reactions was key to understanding the long lifetimes of stars and to reconciling the age of the Sun with the age of the Earth (see Box 3.1). The energy budget of a star represents a balance between... 

Pellerin, L., Magistretti, P. J. How to balance the brain energy budget while spend- 11 ing glucose differently. J. Physiol. 2003,... 

As described above, terms b, c, and d, as well as the viscous dissipation, ev, may be neglected from a first-order energy budget within the shear-layer. The remaining terms suggest that the vortex (and shear-layer) growth will be arrested (D(ks)/Dt = o) when the shear-production balances the canopy dissipation. This balance implies... 

There are also other modules, for instance one of the most detailed parameterisa-tions of urban effects within current numerical models with explicit consideration of the effects of buildings, roads, and other anthropogenic building materials on the urban surface energy budget, was suggested by Masson 2000 [398] in the Town Energy Balance (TEB) scheme. 

This forms the basis of constructing an enthalpy budget in which the total enthalpy flux is compared with the scalar heat flux, 7q(W m-3), obtained from dividing heat flow by size (volume or mass) of the living matter. If account is made of all the reactions and side reactions in metabolism, the ratio of heat flux to enthalpy flux, the so-called energy recovery ( Yq/H = Jq/Jh) will equal 1. If it is more than 1, then the chemical analysis has failed fully to account for heat flux and if it is less than 1, then there are undetected endothermic reactions. Account for all reactions may seem a formidable task, but it should be borne in mind that anabolic processes dissipate insignificant amounts of heat compared with those of catabolism and that ATP production and utilization are balanced in cells at steady-state. Catabolism is generally limited to a relatively few well-known pathways with established overall molar enthalpies. So, as will be seen later, the task is by no means mission impossible. ... 

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