Geometric mean radius

The SFA consists of a hermetically closed stainless steel chamber that can be filled with any transparent liquid or gas of choice. Mica is a preferred substrate in the SFA, though other surfaces, such as single-crystal sapphire plates have also been used [10]. In the SFA, the force acting between the surfaces, mounted in a crossed cylinder configuration, as a function of surface separation is measured. The data obtained are normally plotted as force, FC(D), normalised by the undeformed geometric mean radius of the surfaces, R This quantity is related to the free energy of interaction per unit area, G, between two flat surfaces at the same separation [11] ... 

Equations [4.13] and [4.14] are also supported by some atmospheric measurements. Thus, E. Meszaros (1970) measured the size distribution of the mass of atmospheric sulfate particles by means of a cascade impactor backed up by membrane filters. He found that the geometric mean radius of the distribution averaged by humidity intervals varies as a function of the relative humidity as shown by the points in Fig. 38. The solid line of this figure gives the theoretical relation calculated from equation [4.14] for an ammonium sulfate particle with a dry radius of 0.14 /an, the value found for the geometric mean radius at low relative humidity. The line shows that the particle radius increases by a factor of two at a relative humidity of 80 %. Near 100 % the droplet radius is several times larger than the dry particle size. Comparison of the curve with the experimental points indicates that the behaviour of the atmospheric particle population is well approximated by the theory outlined. It cannot be excluded, however, that the real phase change is less sudden than the theory predicts. 

Variation of geometric mean radius (rso) of sulfate particles as a function of relative humidity (crosses). Solid line represents the theoretical growth of an ammonium sulfate particle with r = 0.14 /jm (E. Meszaros, 1970). (By courtesy of Tellus)... 

The force measured between crossed cylinders (F ), as in the SEA, and between spheres (Fg), as in the MASIF, a distance D apart is normalized by the local geometric mean radius (R). This quantity is related to die fiee energy of interaction per unit area between flat surfaces (W) according to the Deijaguin approximation (30) ... 

Figure 18 Force normalized by local geometric mean radius as a function of surface separation between glass across a concentrated emulsion solution (20 wt % oil and 1.2 wt % phospholipid). The thinner lines correspond to the force measured on separation the dashed line represents the calculated force between two spherical surfaces connected by a capillary condensate in the full equilibrium case [Eq. (25)] and the dotted line represents the force between two spherical surfaces connected by a capillary condensate in the non-equilibrium case [Eq. (26)]. (From Ref. 81, with permission.)...

Nuclei mode has a geometric mean radius between 0.0025 and 0.020 /a and probably results from the condensation of gaseous carbon moieties. 

GMRi = geometric mean radius of conductor i, ft Dij = distance between conductors i and j, ft... 

The vessel b to be autofrettaged with a prtesure sufficient to pla the elastic- dastic interfate at the geometric-mean radius, that is, at /... 

The autofrettage gage pressure required for locating the elastic-pltetic interface at the geometric-mean radius. 

A total amount of200 g of aerosol partides is emitted by the bundle. It was assumed that the initial aerosol distribution at the bundle exit was lo ormal with a geometric mean radius of 0.1 micron and a geometrical standard deviation of 1.7 (1.6 for RAFT). Aerosol particle density is 5.gr/cm3 for TRAPFRANCE smce UO2 release is vast by comparison with all but Cd vapour. 

Although the above equation can be applied to any r, if wechoose r==Rk, that is, r is located at the geometric mean radius of the two cylinders,... 

In order to simplify end corrections in a cup-and-bob viscometer, the ends can be conical. If each end of the bob is the cone of a cone-plate viscometer, what is the ratio of the torque due to the ends of the bob to the torque due to flow in the annulus in the cylindrical part Assume a bob of length L and radius KR, a cup of radius R, and a cone angle of 1 -Assume a Newtonian fluid and refer torque in the annulus to the geometric mean radius. 

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