Sharp Maxima

Because the nonuniform strain due to residual microstress is the major cause of line broadening, we usually find that the broad diffraction lines characteristic of cold-worked metal partially sharpen during recovery. When recrystallization occurs, the lines attain their maximum sharpness. During grain growth, the lines become increasingly spotty as the grain size increases. 

Sharpness can be defined as the attribute which allows the instrument to perform the cutting operation with the minimum effort. The fundamental mechanism of a knife cut is a compressive fracture caused by high pressure from the very small area of the single edge of the knife a razor blade, for example, requires one fine edge, whereas an ice pick requires a sharp point. In order to achieve the maximum sharpness of a blade, the edge angle must be low and the tip radius must be small. ... 

Accommodation n. The adjustment of the eye to obtain maximum sharpness of the retinal imge for n object at which an observer is viewing. One of the important changes involves the shape of the eye lens. 

In practice, it may be possible with care to float somewhat larger particles than those corresponding to the theoretical maximum. As illustrated in Fig. XIII-7, if the particle has an irregular shape, it will tend to float such that the three-phase contact occurs at an asperity since the particle would have to be depressed considerably for the line of contact to advance further. The resistance to rounding a sharp edge has been investigated by Mason and co-workers [62]. 

Maximum Service Temperature. Because the cellular materials, like their parent polymers (204), gradually decrease in modulus as the temperature rises rather than undergoing a sharp change in properties, it is difficult to precisely define the maximum service temperature of cellular polymers. The upper temperature limit of use for most cellular polymers is governed predominantly by the plastic phase. Fabrication of the polymer into a... 

A report on the continuous flash pyrolysis of biomass at atmospheric pressure to produce Hquids iadicates that pyrolysis temperatures must be optimized to maximize Hquid yields (36). It has been found that a sharp maximum ia the Hquid yields vs temperature curves exist and that the yields drop off sharply on both sides of this maximum. Pure ceUulose has been found to have an optimum temperature for Hquids at 500°C, while the wheat straw and wood species tested have optimum temperatures at 600°C and 500°C, respectively. Organic Hquid yields were of the order of 65 wt % of the dry biomass fed, but contained relatively large quantities of organic acids. 

When finest grain stmcture and maximum image sharpness are required, the original is photographed in a large-format camera using a separate sheet of film for each exposure. These cameras are heavier than roll-film cameras and usually require a tripod and/or a controlled studio environment. Common sheet film sizes include 102 x 127 mm (4x5 in.) and 203 x 254 mm (8 x 10 in.). 

Stichlmair uses the ratio of actual velocity to this maximum velocity together with a term that increases entrainment as the distance gets small between the hquid-vapor layer and the tray deck above. His correlation spans a 10 fold range in entrainment. He shows a sharp increase in entrainment at 60 percent of the maximum velocity and attributes the increase to a shift to the spray regime. 

To maintain maximum sealing effieieney, it is essential that the labyrinth lands maintain sharp edges in the direetion of the flow. This requirement is similar to that in orifiee plates. A sharp edge provides for maximum vena eontraeta effeet, and lienee maximum restrietion for the leakage flows. (Figure 13-22.)... 

General. With simple instrumentation discussed here, it is not possible to satisfactorily control the temperature at both ends of a fractionation column. Therefore, the temperature is controlled either in the top or bottom section, depending upon which product specification is the most important. For refinery or gas plant distillation where extremely sharp cut points are probably not required, the temperature on the top of the column or the bottom is often controlled. For high purity operation, the temperature will possibly be controlled at an intermediate point in the column. The point where AT/AC is maximum is generally the best place to control temperature. Here, AT/AC is the rate of change of temperature with concentration of a key component. Control of temperature or vapor pressure is essentially the same. Manual set point adjustments are then made to hold the product at the other end of the column within a desired purity range. The technology does exist, however, to automatically control the purity of both products. 

Bearings normally have a specified clearance range. Allowing clear ances to exceed the specified maximum clearance may encourage the onset of rotor dynamics problems. Dams in dam type bearings are very critical. The edge of the relief must be square and sharp, not rounded. The clearance of this bearing is also quite sensitive and must remain inside the specified limits for stability. 

Higher concentrations of solute move through the system more rapidly, thus reducing the retention time of the peak maximum which produces a peak with a sharp front and a sloping tail. 

Higher concentrations of solute move through the system more slowly displacing the peak maximum to a later retention time and, thus, a peak is produced with a sloping front and a sharp back. 

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