Pumps high-energy

Note In the case of high-energy pumps (see 2.1.15), and multistage pumps, it may not be feasible to test at shutoff. 

Population inversion is difficult not only to achieve but also to maintain. Indeed, for many laser systems there is no method of pumping which will maintain a population inversion continuously. For such systems inversion can be brought about only by means of a pumping source which delivers short, high-energy pulses. The result is a pulsed laser as opposed to a continuous wave, or CW, laser which operates continuously. 

Lasers act as sources and sometimes as amplifiers of coherent k—uv radiation. Excitation in lasers is provided by external particle or photon pump sources. The high energy densities requked to create inverted populations often involve plasma formation. Certain plasmas, eg, cadmium, are produced by small electric discharges, which act as laser sources and amplifiers (77). Efforts that were dkected to the improvement of the energy conversion efficiencies at longer wavelengths and the demonstration of an x-ray laser in plasma media were successful (78). 

The principal advantage of self-induced spray scrubbers is the efim-ination of a pump for recirculation of the scrubbing liquid. However, the designs for high-energy service are somewhat more complex and less flexible than those for venturi scrubbers. 

Garbers, A. W. and A. K Wasfi, Preventing Cavitation in High Energy Centrifugal Pumps, Hydrocarbon Processing, V. 69, No. 7, 1990. 

The plasma membrane Ca2+-ATPase pump effects outward transport of Ca2+ against a large electrochemical gradient for Ca2+. The mechanism of the pump involves its phosphorylation by ATP and the formation of a high-energy intermediate. This basic mechanism is similar for both the plasma membrane and ER pumps however, the structures of these distinct gene products are substantially different. As discussed below, the ER pump, sometimes called a sarcoendoplasmic reticulum Ca2+-ATPase (SERCA) pump, is inhibited potently by certain natural and synthetic toxins that do not affect the plasma membrane pump. The plasma membrane pump, but not the SERCA pump, is controlled in part by Ca2+ calmodulin, allowing for rapid activation when cytoplasmic Ca2+ rises. 

Source of high-energy electrons, ion accelerator, magnetic/electrostatic analyser, detector and recorder, high vacuum pumping system. 

The upward arrows in the figure indicate the pumping channels to various high energy levels by flashlamp (0.5 /tim) or semiconductor lasers (0.8 /rm), where Nd + ions display strong absorption transitions. The downward arrow indicates the widely used laser emission at 1.06 /xm, associated with the -> " ln/2 transition. In addition, laser action is also generally possible from the same " F3/2 level to the " 19/2 state at around 0.9 /xm and to the 113/2 state at around 1.3 /xm. 

---