Pumping energy

Fig. 9. Impact of excess design capacity on pump energy use, where A corresponds to actual operating flow, and D to the design point if the designer calls...

Power requirements for spiral plants are low, consisting primarily of pumping energy and possibly a thickener or other pulp-handling equipment associated with the flowsheet. 

Vacuum systems (Fig. 21-12h) are characterized by material moving in an air stream of pressure less than ambient. The advantages of this type are that all the pumping energy is used to move the product and that material can be sucked into the conveyor line without the need of a rotaiy feeder or similar seal between the storage vessel and the conveyor. Material remains suspended in the air stream until it reaches a receiver. Here, a cyclone separator or filter (Fig. 21-12c) separates the material from the air, the air passing through the separator and into the suction side of the positive-displacement blower or some other power source. 

A rule of thumb for a modern ED stack is that the pumping energy is roughly 0.5 kWh/m, about the same as is reqmred to remove 1700 mg/f dissolved salts. 

A bicyclist has to expend energy to cycle up a steep hill. The energy the cyclist expends is determined by the product of the power the cyclist develops and the time the cyclist is pumping (energy = power x time). The cyclist may choose to develop a relatively large amount of power and pump for a short period of time. Or he may prefer to take it easy developing a... 

Figure 10-14. Inset Phololumincsccncc spectrum for low excitation pulse energy EP Main part (a) displays the spectrum for pump pulse energies well below the lasing threshold while (b) shows the spectrum obtained lor excitation with a pump energy close to the lasing threshold (c) presents the single mode-lasing spectrum emitted when the device is pumped well above threshold. The dashed lines indicate the zero line which is arbitrarily shifted in case of (b) and (c).

We assume that standard Coulomb-correlated models for luminescent polymers [11] properly described the intrachain electronic structure of m-LPPP. In this case intrachain photoexcitation generate singlet excitons with odd parity wavefunctions (Bu), which are responsible for the spontaneous and stimulated emission. Since the pump energy in our experiments is about 0.5 eV larger than the optical ran... 

Above a pump energy of 20 pJ for the incident laser beam a strong spectral narrowing of the PL-spcclra of m-LPPP could be detected. The recorded spectra... 

For this study, thin films were deposited onto glass substrates. The as-deposited films showed no spectral narrowing at any pump energy up to the damage threshold. Stimulated emission was observed only in annealed films. The spol-to-spot reproducibiliiy of the measured characteristics was good, and we could measure with excitation energies of up to 4 mJ (1.8 mm beam diameter) without visual damage of the illuminated spot. 

The increase in pumping energy is smaller than for turbulent flow but is still large. The power input to a unit volume of fluid increases by a factor of S. ... 

In laminar flow, the pressure drop is constant when scaleup is carried out by geometric similarity. In turbulent flow, it increases as the square root of throughput. There is extra pumping energy per unit volume of throughput, which gives... 

Pump Energy Requirements If there is no forced convection within the cells, the polarization limits the current density to a very uneconomic level. Conversely, if the circulation rate is too high, the... 

The energy cost is determined from the pumping energy requirement, which is in turn determined from the Bernoulli equation ... 

The total pumping energy cost per year is therefore... 

Fig. 19.5 The spectral position of the laser emission and the threshold curves (in the insets) for (a) an etched resonator with OD 75 pm and the wall thickness of 3.8 pm having threshold at pump energy density of 1 pj/mm2 and (b) unetched resonator with OD 75 pm and the wall thickness of 5 pm with a threshold of 25 nJ/mm2. Reprinted from Ref. 20 with permission. 2008 International Society for Optical Engineering...

As steady-state can only be maintained by the concurrence of some pumping energy, it has been associated with many life processes of no change. Conversely, equilibrium would correspond with a no-change situation of death . 

Pump and treat hazardous waste management, 25 845 Pump-around streams, 13 223 Pump calculation worksheet, 21 56 Pump energy level, 14 695 Pump head, total developed, 21 57-58 Pumping, 14 658-659... 

Radial and thrust bearing speed and life within limits for rolling element bearings and Pump energy density below limit Rolling element radial and thrust... 

Films of this material can be optically pumped to induce amplified spontaneous emission at 535 nm, as shown in Figure 14. The lasing threshold (Eth) h the pump energy at which amplified spontaneous emission is observable, and depends strongly, among other factors, upon the lifetime of the polymer excited state. A longer excited state lifetime allows more emissive excitons to build up in... 

Chen, L. and Wu, C., Optimal performance of an endo-reversible Carnot heat pump. Energy Conversion and Management, 38(14), 1439-1444, 1997. 

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