Greenwald limit

The reason behind the widely different extrapolations to ITER by the v ped (neo) and T ont scalings is that with increasing device size, and for discharges at similar normalized densities to the Greenwald limit, the pedestal temperature increases approximately as Tped r J R2 [16]. As a consequence, the pedestal collisionality decreases as v ped (neo) R 3, while the ion... 

Many finely divided metal powders in suspension in air are potential e] losion hazards, and causes for ignition of such dust clouds are numerous [Hartmann and Greenwald, Min. MetalL, 26, 331 (1945)]. Concentration of the dust in air and its particle size are important fac tors that determine explosibility. Below a lower Umit of concentration, no explosion can result because the heat of combustion is insufficient to propagate it. Above a maximum limiting concentration, an explosion cannot be produced because insufficient oxygen is available. The finer the particles, the more easily is ignition accomplished and the more rapid is the rate of combustion. This is illustrated in Fig. 20-7. 

Several studies have shown that the water content of human, rat and dog arteries is increased in hypertension, and this increased water content may be associated with an increased wall thickness [64, 65]. Due to the limitations in studying samples from human subjects, animal models (mainly rats) have been employed. Mallov [66] found that the aorta from hypertensive rats had more smooth muscle than normal aorta. Greenwald and Berry [67] reported increased elastin and decreased collagen content in the aorta from spontaneous hypertensive rats when compared with the normal aorta. Wolinsky [25] observed an increase in the absolute amounts of both medial elastin and collagen contents in hypertensive rats. However, the relative percentage of these elements remained essentially constant. Experimental studies [67-69] showed an increase in vessel stiffness with the development of hypertension. This increase in vessel stiffness results in a smaller vessel diameter for a given distending pressure, i.e. a decrease in the distensibility [70]. 

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