Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

S , axis of rotation

In contrast, limestones from the Equatorial Pacific show much heavier Zn. The surface sediment of the carbonate-dominated core TT013 19MC in the Equatorial Pacific (1° 52 S, 139° 43 W, z = 4500 m) has a 5 Zn value of 0.79%o, while Pichat et al. (2003) analyzed the carbonate fraction of the core OOP 849 (0° 11.59 N, 110° 31.18 W, z = 3851 m) over the last 175 ka and found a downcore variation from 0.6 0.2 to 1.2 0.2%o (Fig. 6). The reproducibility of the measurements is consistent with the internal errors. Small scale fluctuations along the core are dominated by two significant 35.2 and 21.2 ka periods. The former is difficult to assign to a known astronomical feature but the latter corresponds to a forcing by the precession of the Earth s axis of rotation. [Pg.417]

Viscoelastic fluids have elastic properties in addition to their viscous properties. When under shear, such fluids exhibit a normal stress in addition to a shear stress. For example, if a vertical rod is partly immersed and rotated in a non-viscoelastic liquid the rod s rotation will create a centrifugal force that drives liquid outwards toward the container walls, as shown in Figure 6.16(a). If, on the other hand, the liquid is viscoelastic then as the liquid is sheared about the rod s axis of rotation, a stress normal to the plane of rotation is created which tends to draw fluid in towards the centre. At some rotational speed, the normal force will exceed the centrifugal force and liquid is drawn towards and up along the rod see Figure 6.16(b). This is called the Weissenberg effect. Viscoelastic fluids flow when stress is applied, but some of their deformation is recovered when the stress is removed [381]. [Pg.178]

In 1977, astronomers discovered that Uranus is surrounded by a system of rings similar to those of Saturn. They lie in a concentric pattern around the planet s equator. Uranus s axis of rotation is parallel with its plane of revolution, rather than perpendicular to it, like Earth s. In other words, instead of spinning like a top on its path around the Sun, as Earth does, Uranus "rolls along it like a barrel. Consequently, the planet s rings form a "bull s-eye pattern pointing at the Sun. [Pg.156]

High-Precision Machining by Measuring and Compensating the Error Motion of Spindle s Axis of Rotation in Radial Direction... [Pg.347]

As can be seen in Fig. 29.2, before cutting, all the displacement profiles involve periodical type of fluctuation. These periodic fluctuations are related to the error motion of a spindle s axis of rotation in radial direction and roundness errors of the target surface. During cutting, it is observed that the displacement profile shifts but it returns to its original position after the end of cutting. [Pg.350]

Fufcrum is the truck s axis of rotation when it tips over. [Pg.595]

Such a device with three orthogonal Sagnac interferometers can be used as a navigation system, because the Earth s rotation causes a Sagnac effect that depends on the angle between the surface normal n and the Earth s axis of rotation > i.e., on the geographical latitude. [Pg.150]

Pitch diameter, rolling elements The diameter of the pitch circle generated by the center of a rolling element as it traverses the bearing s axis of rotation. [Pg.530]

On Saturn the thermal emission and albedo measurements are much more complicated then those of Jupiter. Complications arise primarily due to the presence of the rings and the tilt of Saturn s axis of rotation with respect to its orbital plane. The rings cast shadows and reflect sunlight onto Saturn. However, these effects vary over the orbit of Saturn around the Sun. The Voyager measurements occurred at one particular point on that orbit, but only the mean orbital values are pertinent to the energy balance of Saturn. First, it was necessary to remove the effects of the rings from the measurements of the thermal emission and the albedo of Saturn. Then the effect of the rings needed to be introduced over the full orbital motion of Saturn (Hanel et al., 1983). An effective temperature of 95.0 0.4 K was found. [Pg.461]

The obvious way to form a similarity between the Wigner rotation matrix and the adiabatic-to-diabatic transformation mabix defined in Eqs. (28) is to consider the (unbreakable) multidegeneracy case that is based, just like Wigner rotation matrix, on a single axis of rotation. For this sake, we consider the particular set of T matrices as defined in Eq. (51) and derive the relevant adiabatic-to-diabatic transfonnation matrices. In what follows, the degree of similarity between the two types of matrices will be presented for three special cases, namely, the two-state case which in Wigner s notation is the case, j =, the tri-state case (i.e.,7 = 1) and the tetra-state case (i.e.,7 = ). [Pg.686]

Since the radial acceleration functions simply as an amplified gravitational acceleration, the particles settle toward the bottom -that is, toward the circumference of the rotor-if the particle density is greater than that of the supporting medium. A distance r from the axis of rotation, the radial acceleration is given by co r, where co is the angular velocity in radians per second. The midpoint of an ultracentrifuge cell is typically about 6.5 cm from the axis of rotation, so at 10,000, 20,000, and 40,000 rpm, respectively, the accelerations are 7.13 X 10, 2.85 X 10 , and 1.14 X 10 m sec" or 7.27 X 10, 2.91 X 10, and 1.16 X 10 times the acceleration of gravity (g s). [Pg.635]

When experimental data are not available, methods of estimation based on statistical mechanics are employed (7,19). Classical kinetic theory suggests a contribution to CP of S R for each translational degree of freedom in the molecule, a contribution of S R for each axis of rotation, and of R for each vibrational degree of freedom. A cmde estimate of CP for small molecules can be obtained which neglects vibrational degrees of freedom ... [Pg.235]

Figure 11.3 illustrates the classification of the MOs of butadiene and cyclobutene. There are two elements of symmetry that are common to both s-cw-butadiene and cyclobutene. These are a plane of symmetry and a twofold axis of rotation. The plane of symmetry is maintained during a disrotatory transformation of butadiene to cyclobutene. In the conrotatory transformation, the axis of rotation is maintained throughout the process. Therefore, to analyze the disrotatory process, the orbitals must be classified with respect to the plane of symmetry, and to analyze the conrotatory process, they must be classified with respect to the axis of rotation. [Pg.610]

If the centrifuge operates at 4000 rpm and the particle s distance from the axis of rotation is 0.25 m, the settling velocity is only 0.01 m/sec, which corresponds to ... [Pg.532]

We have an emulsion of oil in water that we need to separate. The oil droplets have a mean diameter of lO " m, and the specific gravity Of the oil is 0.91. Applying a sedimentation centrifuge to effect the separation at a spedd of 5,000 rpm, and assuming that the distance of a droplet to the axis of rotation is 0.1 m, determine the droplet s radial settling velocity. [Pg.594]

S , Rotation of the molecule through an angle 360°/n followed by reflection of all atoms through a plane perpendicular to the axis of rotation the combined operation (which may equally follow the sequence reflection then rotation) is called improper rotation-,... [Pg.1290]

Centrifugal pumps can be further classified by physical design or axially split, radially split and whether the axis of rotation of the impeller(s) is vertical or horizontal. [Pg.473]

Fig. 9-5. The General Electric XRD-5 D/S spectrogoniometer arranged for x-ray emission work. Since the axis of rotation is- vertical, heavy auxiliary equipment may be attached without disturbing the apparatus. (Courtesy of X-ray Dephrtment, General Electric Company, Milwaukee, Wise.)... Fig. 9-5. The General Electric XRD-5 D/S spectrogoniometer arranged for x-ray emission work. Since the axis of rotation is- vertical, heavy auxiliary equipment may be attached without disturbing the apparatus. (Courtesy of X-ray Dephrtment, General Electric Company, Milwaukee, Wise.)...
While the matrix R does not explicitly involve the axis of rotation along which e extends, nor the angle of rotation 6, it is known (from a theorem of Euler s) that every R is equivalent to a single rotation definable geometrically by an e and a 0. [Pg.396]

If the s-coordinate is za at the point on the axis of rotation which coincides with the free surface of the liquid (or the extension of the free surface), then the corresponding pressure Pq must be that of the atmosphere in contact with the liquid. [Pg.52]

He considered that the rapid flame propagation could be achieved with the same mechanism as vortex breakdown. Figure 4.2.2 schematically shows his vortex bursting mechanism [4,5]. When a combustible mixture rotates, Ihe pressure on the axis of rotation becomes lower than the ambient pressure. The amount of pressure decrease is equal to max in Rankine s combined vor-fex, in which p denotes fhe unburned gas density and Vg denotes the maximum tangential velocity of the vortex. However, when combustion occurs, the pressure on the axis of rofafion increases in the burned gas owing to the decrease in the density, and becomes close to the ambient pressure. Thus, there appears a pressure jump AP across the flame on fhe axis of rotation. This pressure jump may cause a rapid movement of the hot burned gas. By considering the momentum flux conservation across the flame, fhe following expression for the burned gas speed was derived ... [Pg.46]

Thus, it should be noted that the flame propagation in combustible vortex rings is not steady, but "quasi-steady" in the strict sense of the word. This may explain why prediction 9, based on the momentum flux conservation can better describe the flame speed for large values of Vg than prediction 4, which adopts the Bernoulli s equation on the axis of rotation. [Pg.54]

Consider a rotation of the earth around the z-axis in which every particle, elementary volume, of the earth moves along the horizontal circle with the radius r. Our first goal is to find the distribution of forces inside the earth and with this purpose in mind we will derive an equation of motion for an elementary volume of the fluid. Let us introduce a Cartesian system of coordinates with its origin 0, located on the z-axis of rotation. Since this frame of reference is an inertial one, it does not move with the earth, we can write Newton s second law as... [Pg.59]

If a proper rotation is combined with a reflection with respect to the axis of rotation, it is called an improper rotation The matrix representation of silvan operation is found simply by replacing 1 by -1 in Eq. (104), The Scftfllfllies symbol for an improper rotation by y is S /tp- Hence, matrix the representation of an improper counter-clockwise rotation by y is of the form ... [Pg.92]


See other pages where S , axis of rotation is mentioned: [Pg.147]    [Pg.64]    [Pg.986]    [Pg.435]    [Pg.475]    [Pg.348]    [Pg.358]    [Pg.179]    [Pg.147]    [Pg.64]    [Pg.986]    [Pg.435]    [Pg.475]    [Pg.348]    [Pg.358]    [Pg.179]    [Pg.685]    [Pg.91]    [Pg.1781]    [Pg.195]    [Pg.432]    [Pg.526]    [Pg.527]    [Pg.531]    [Pg.538]    [Pg.191]    [Pg.149]    [Pg.155]    [Pg.882]    [Pg.816]   
See also in sourсe #XX -- [ Pg.145 ]




SEARCH



Axis of rotation

Rotation axis

© 2024 chempedia.info