Pumps/pumping energy conservation

Capital investment, capital costs, operating costs, return on investment, and energy conservation have all been discussed (6). In the economic analysis, the speed of each type of pump considered is normalized to 1 m /s as a common basis. 

FIGURE 19-30 Heat generation by uncoupled mitochondria. The uncoupling protein (thermogenin) of brown fat mitochondria, by providing an alternative route for protons to reenter the mitochondrial matrix, causes the energy conserved by proton pumping to be dissipated as heat. 

Heat pump - [HEAT-EXCHANGE TECHNOLOGY - NETWORK SYNTHESIS] (Vol 12) -role m process energy conservation [PROCESS ENERGY CONSERVATION] (Vol 20)... 

Although the presented numerical approach to the coupled master equations has shown that a turnover feature can be seen in vibronic dynamics appearing in the calculated pump-probe stimulated emission spectra as a function of the energy gap between the two relevant vibronic states. It is found that vibronic quantum beats cannot be observed when the energy gap becomes larger in which situation it leads to smaller Franck-Condon overlaps between the energy conserved levels. 

When we consider that we lose work potential in chemical reactors, in heat exchangers, and in mixing operations and combine this with the need for work in separation processes, pumping, and compression, it becomes dear that chemical processes are usually very inefficient from an energy standpoint. Of course, energy conservation is usually of secondary importance in chemical processing safety, quality, and productivity are more important, Nevertheless, it is economically sound... 

As mentioned previously, the incident pump and Stokes laser beams must be aligned in a precise manner so that the CARS generation process is properly phased. Since gases are virtually dispersionless, i. e. the refractive index is nearly a constant over a wide frequency range, the photon energy conservation condition ujas = in-... 

As in the case of the ATP synthase, the most convincing evidence for the function of the respiratory chain as an autonomous proton pump comes from the ability to purify energy-conserving segments of the chain and reconstitute them into artificial bilayers with the recovery of their proton translocating capacity [21,22]. 

Fig. 3.6. Principle of energy conservation by cytochrome oxidase. The approximate location of haems a and Qj are indicated with respect to the membrane (see the text). Cytochrome c is also shown (upper left) at the approximately correct distance from haem a. The 40 A lipid domain of the membrane is indicated by horizontal lines. The pathway of electron transfer is shown by dotted arrows reduction of dioxygen by thin arrows. Thick black arrows symbolise the redox-linked proton-pumping function. The thick white arrow shows the uptake of protons into the haem aj/Cug site. See the text for details. (From Ref. 92).

This energy-conserving function is simply a consequence of two topological features electron donation takes place from the C side, and proton donation for conversion of Oj to water from the M side (for the evidence, see below). The position of the haem a 3 centre with respect to the membrane surfaces then determines to what extent the reaction requires electron and proton translocation. Since the evidence points strongly towards the positioning of haem a3 near the C side (Section 3.6), the mechanism involves mainly proton translocation, and electron translocation only to a lesser degree. Hence, not only the thermodynamical, but also the structural features of this mechanism resemble those of a proton pump . It differs from the... 

Less clear is the pathway of cyclic electron transfer around PSI. This pathway involves cyt. 6 and cyt. /, and an energy conserving site (demonstrated by the formation of ATP, proton pumping and a slow rising electronchromic signal. 

The Na K ATPase of the plasma membrane and the Ca " transporters of the sarcoplasmic and endoplasmic reticulums (the SERCA pumps) are examples of P-type ATPases they undergo reversible phosphorylation during their catalytic cycle and are inhibited by the phosphate analog vanadate. F-type ATPase proton pumps (ATP synthases) are central to energy-conserving mechanisms in mitochondria and chloroplasts. V-type ATPases produce gradients of protons across some intracellular membranes, including plant vacuolar membranes. 

The blue oxidases are soluble extracellular enzymes (see, e.g., Messerschmidt ) whereas the terminal respiratory oxidases are membrane bound and use the free energy available from this reaction to pump protons across the membrane. The transmembrane proton and voltage gradient generated by the oxidase and other components of the aerobic respiratory chain is converted directly to more useful forms by a number of membrane-bound energy-conserving systems, such as the ATP synthase and secondary active transport systems (see, e.g., Calhoun et... 

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