Internal radius

Fig. 3. Schematic diagram of an ion trap where A and B represent end cap electrodes, C the ring electrode, Tq the internal radius of C, and the internal...

The viscosity of molten BeF2 and LiF-BeF2 mixture has been measured with this method. In this experiment, cylindrical spindles of Inconel, varying in radius between 0.158 and 1.65 cm, were rotated in nickel vessels of 2.05 cm internal radius. 

The external diameter of the tube and its wall thickness determine the pressure which it will stand. Failure of a tube is due to the tension at the surface becoming too great. For a cylinder of internal radius r and external radius R, and vwth an internal pressure in the cylinder of P, the maximum circumferential (or hoop) tension S (see A. Morley, 1940) on the inner surface of the cylinder is... 

Bronchial smooth muscle tone. Changes in bronchial smooth muscle tone are particularly important in the bronchioles compared to the bronchi. Recall that the walls of the bronchioles consist almost entirely of smooth muscle. Contraction and relaxation of this muscle has a marked effect on the internal radius of the airway. An increase in bronchial smooth muscle tone, or bron-choconstriction, narrows the lumen of the airway and increases resistance to... 

What is the physical meaning of these data The internal radius is 3.7 mn smaller than the external one, which corresponds to the thickness of the bilayer. Liposomes with an external radius of 100 mn are made up of 336 000 lipid molecules, and in this case each compartment has an internal volume of 3.74 x 10 p,l. This means that the total internal aqueous volume in one liter of a 10 mM POPC solution is 66.9 ml, namely 6.69% of the total volume. 

The hoop stress can be obtained by considering an elemental portion of the cylinder wall, 5x, subtending an angle SO, at the center and at an angle 9 with XX (see Figure 8.8). The internal radius of the cylinder is r and the length of the unit is L. Since the pressure of the fluid always acts perpendicular to the surface of contact, the total pressure, P, normal to the elemental section is given by... 

AT = Ti - T0 is the steady-state temperature difference between the internal radius R, and the external radius R0. When the above three equations are derived it is assumed that the cylinder is made of an isotropic and initially stress free material and the temperature does not vary along the cylinder axis. Further the effect of temperature on a, the coefficient of thermal ex-... 

A fast chemical sensor that operates at a reduced pressure of 50 torr (6700 Pa) and with a flow of 1 standard liter per minute must be maintained in an instrument shelter. Considerations of flow distortion require that 10 m separate the sensor from its intake on the tower near the sonic anemometer. Three ducting arrangements can be considered. The first would involve drawing air along 10 m of 1/4-inch tubing (0.2 cm internal radius) and controlling the flow and pressure at the sensor itself. The second option would place the pressure-flow controller at the inlet and allow the inlet intake to flow at the reduced pressure. The third course would be to use a... 

To estimate how high water will rise in a vertical tube of internal radius 2.0 mm at room temperature, we take the surface tension of water from Table 5.3 and insert if in the expression for h in Eq. 6 the acceleration of free fall is given inside the back cover, and the density of water is 1.0 g-cm-3, corresponding to 1.0 X 103 kg-m 3. Recall that 1 N = 1 kg-m-s-2. Then... 

Fig. 5 shows a vertical tube of internal radius r dipping into a liquid. If a bubble is blown at the end of this tube it will have the form of a segment of a sphere, if the radius of the tube is small. The radius of this sphere will first decrease, until the bubble becomes hemispherical. Further growth of the bubble will increase the radius. By equation (3) the pressure in the bubble will be a maximum when the radius is a minimum, that is, when the radius of the bubble is equal to that of the tube. The bubble will be unstable when it has grown beyond the hemispherical shape, because the pressure decreases as more air passes into it. Hence the maximum pressure attainable in a bubble blown on a small tube is... 

External radius of disk Internal radius of disk ... 

Selecki and Wasiak [54] have developed a modification of this technique which they named capillary method. Under the influence of a reduced pressure the foam moves continuously through a capillary tube with a known internal radius rin. The foam in the capillary is transformed into bubbles with extended cylindrical shape. By a lamp and two phototransistors the rate of film movement vy is measured, thus enabling to determine the equivalent diameter of each bubble... 

The standard way to decrease the pressure drop is to use a catalyst in the form of hollow cylinders or rings. The expected gain in void fraction, when full cylinders with a height H and radius Ru are replaced by the hollow cylinders of the same external sizes and an internal radius Rt, can be calculated on the basis of some geometrical considerations. The void fractions of beds packed with the cylinders and rings are ... 

If a catalyst in a form of solid cylinders is replaced by hollow cylinders with an optimal internal radius, the reactor productivity will increase although the total mass of catalyst decreases. For example, the use of hollow cylinders with an internal radius of 035RU instead of solid cylinders of the same external size for the water-gas shift reaction at a pressure of 3 MPA and a temperature of 417 °C may increase the effectiveness of the unit reactor volume by 18%. This is particularly important for processes under elevated pressures, because of the strong dependence of the reactor cost on its volume [17]. 

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