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Stationary plane

The method described above for the atomic system can be extended to a macroscopic system shown in Fig. 7 where a spherical body is connected via the spring ktoa supporter in relative motion with respect to a stationary plane. [Pg.170]

FT-IR utilizes the Michelson interferometer rather than the grating or prism of the dispersive system. The Michelson interferometer has two mutually perpendicular arms. One arm of the interferometer contains a stationary, plane mirror the other arm contains a moveable mirror. Bisecting the two arms is a beamsplitter which splits the source beam into two equal beams. These two light beams travel their respective paths in the arms of the interferometer and are reflected back to the beam splitter and on to the detector. The two reunited beams will interfere constructively or destructively, depending on their path differences and the wavelengths of the light. When the path lengths in the two arms are the same, all of the frequencies... [Pg.74]

A similar treatment for the stationary plane electrode has never been proposed as far as we are aware. In view of the expression for the diffusion layer, 5 = (ntDm )v2, it could be inferred that the convection term should be given by F(x) = (x/21) because 5 is formally identical to [162]... [Pg.336]

The limiting case corresponding to eqn. (208f) is identical to the result of the so-called reaction layer approach [147, 163], which appears to be valid if ktt > ca. 25 in the case of the DME and kit > ca. 12 in the case of the stationary plane electrode. Similar conditions were deduced from other considerations concerning the reaction layer concept. It appears that Jacq s expressions for the lower ftft values provide a useful refinement. It has, however, not been checked on what conditions the original assumptions, cP(x) f(f) and cQ(a ) = f(f), are permitted. [Pg.337]

Equation (215) holds for the stationary plane electrode. For the expanding plane electrode (an approximation for the DME), the inverse transformation is preferably conducted via the convolution integrals equation (206a) and the approximated form of eqn. (206b), which are substituted into the inverse transforms of eqns. (211). Subsequently, eqns. (211) are inserted into the rate equation (198a), yielding the expression... [Pg.339]

The theoretical description of any mechanism is most complex at the DME. Solutions using the stationary plane, expanding plane and the expanding sphere models have been obtained and exhibit some differences, the last being, of course, the most rigorous [168—170]. The EEE mechanism at stationary and expanding planes has also been discussed [171, 172]. Immobilization or adsorption of the intermediate in the EE mechanism is a realistic possibility [173]. [Pg.407]

The word viscosity comes from the Latin word for mistletoe, viscum. Anyone familiar with this plant is aware that it exudes a viscous sticky sap when harvested. Viscosity is defined after Isaac Newton in his Principia as the ratio of stress to shear rate and is given the symbol T. Stress (a) in a fluid is simply force/area, like pressure, and has the units of pascals (Pa S.I. units) or dynes/cm2 (c.g.s.). Shear rate or strain rate (y or dyldt) is the differential of strain (y) with respect to time. Strain is simply the change in shape of a volume of fluid as a result of an applied stress and has no units. The shear rate is in fact a velocity gradient, not a flow rate. It has the bizarre units of 1/time (sec-1) and is the velocity at a given point in the fluid divided by the distance of that point from the stationary plane. [Pg.1137]

Example 6.2 The Synthesis of the Inverse Single Screw Pump There is, however, another, more elegant way to relax the channel-length constraint, as shown in Fig. E6.2. After one circumference, a flow channel formed by the moving and stationary planes of a given width can be twisted helically by an amount equal to the width of the channel to create a much longer helical channel on the same roll or shaft. The channel itself can be simply machined onto the inner surface of the stationary cylinder or barrel. [Pg.241]

Fig. E6.3a The synthesis of a hollow cylinder pump, (a) The building block (b) a rotating hollow cylinder forms the moving plane (c) the stationary plane is formed by the outer surface of a solid stationary shaft. A channel block separates inlet and outlet. Feeding and discharge are carried out through slits in the shaft leading to axial holes drilled in the shaft (d) the two surfaces that form a shallow curved channel are bounded by a sidewall or flight running along the circumference of the shaft. Fig. E6.3a The synthesis of a hollow cylinder pump, (a) The building block (b) a rotating hollow cylinder forms the moving plane (c) the stationary plane is formed by the outer surface of a solid stationary shaft. A channel block separates inlet and outlet. Feeding and discharge are carried out through slits in the shaft leading to axial holes drilled in the shaft (d) the two surfaces that form a shallow curved channel are bounded by a sidewall or flight running along the circumference of the shaft.
Fig. E6.5b The synthesis of a flat spiral pump from building block 1. (a) A section of the curved channel formed by a stationary plane and the rotating disk plane (b) the extension of the channel into a flat spiral (c) outside view of the flat spiral pump, with the spiral channel machined into the surface of one disk and another closely spaced rotating disk covering it. Fig. E6.5b The synthesis of a flat spiral pump from building block 1. (a) A section of the curved channel formed by a stationary plane and the rotating disk plane (b) the extension of the channel into a flat spiral (c) outside view of the flat spiral pump, with the spiral channel machined into the surface of one disk and another closely spaced rotating disk covering it.
Equation (6.21) is valid for any uniformly accessible electrode, including dropping electrodes, stationary plane electrodes, various hydro-... [Pg.107]

MOLAL FLOW RATE, VELOCITY, AND FLUX. If the total molal flux, in moles per unit time per unit area in a direction perpendicular to a stationary plane, is denoted by N and the volumetric average velocity by mq,... [Pg.650]

For components A and crossing a stationary plane, the molal fluxes are... [Pg.650]

Difliisivities are defined, not with respect to a stationary plane, but relative to a plane moving at the volume-average velocity Mq. By definition there is no net volumetric flow across this reference plane, although in some cases there is a net molar flow or a net mass flow. The molar flux of component A through this reference plane is a diffusion flux designated and is equal to the flux of A for a stationary plane [Eq. (21.2)] minus the flux due to the total flow at velocity Mq and concentration... [Pg.650]

The solution to this problem for a stationary plane electrode (semi-infinite linear diffu sion) is (47)... [Pg.568]

This lubrication result was obtained by assuming a spherical particle approaching a stationary plane surface at constant velocity under the action of a constant applied force. The fluid between the spherical particle and the surface is squeezed out radially in the direction essentially parallel to the plane surface. In their calculation, Charles Mason approximated the sphere by a parabola of the same radius as the particle at the apex. [Pg.244]

Recently, the microelectrophoretic technique received two improvements [21]. First, electrodes were designed in such a manner that micrometer-sized bubbles are produced over the entire cross-section of the electrophoresis cell, which allows to select a bubble easily in the stationary plane. Second, a motorized vertical translation stage controlled by a computer is implemented. Thus, when bubbles rise, the electrophoresis cell mounted on the translation stage is made to move downward so that the bubbles can be kept in the field of view of the microscope. As a result, the movement of bubbles with diameters up to 80 p-m can be readily followed and bubble trajectory can be traced for 4-8 sec. [Pg.499]

This parabolic Poiseuille-like profile gives a stationary plane for... [Pg.284]

When b is not infinitely larger than h the physics remains, identical, but the stationary planes are called Komagata planes, and are located closer from the wall. [Pg.284]

Even though cube comers largely eliminate the effect of tilt, lateral displacements produce a shear that has a similar effect on the interferogram. In practice, it is easier to meet the tolerance on lateral displacements than on tilts, so that retroreflectors have a definite experimental advantage over plane mirrors for a given drive. Steel [3] has suggested a combination of a movable cube comer and stationary plane mirrors that introduces neither shear nor tilt. An interferometer based on this principle, shown... [Pg.113]


See other pages where Stationary plane is mentioned: [Pg.123]    [Pg.90]    [Pg.308]    [Pg.340]    [Pg.460]    [Pg.135]    [Pg.44]    [Pg.148]    [Pg.135]    [Pg.22]    [Pg.224]    [Pg.499]    [Pg.502]    [Pg.122]    [Pg.122]    [Pg.262]    [Pg.119]   
See also in sourсe #XX -- [ Pg.284 ]




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