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Right-handed axial system

Right-handed axial system A system of axes, usually orthogonal (at right angles to each other), that are designated 2 , y, and z, in such an order that x is converted to y and y is converted to z in the same manner that a right-handed screw (moving clockwise into a piece of wood) would proceed (with a to y as the clockwise motion and Z the direction into the wood). [Pg.67]

The use of a reference axial system, whether right- or left-handed, is completely analogous to the Cahn, Ingold, and Prelog convention (75-77) regarding the specification of the absolute configuration of chiral molecules R and S as depicted in Scheme 11 for molecules with large (L), medium (M), and small... [Pg.39]

Notice that the right-hand side of Eq. (34) is equal to the ratio of the transformed concentration at the second measurement point to the transformed concentration at the first measurement point. In the terminology of control engineering, this quantity is the transfer function of the system between Xo and Xm- The Laplace-transform method is possible because the diffusion equation is a linear differential equation. Thus, the right-hand side of Eq. (34) could in principle be used in a control-system analysis of an axial-dispersion process. [Pg.116]

Fig. D.5 The mesh network to solve the momentum equation for the axial velocity distribution in a rectangular channel. As illustrated, the control volumes are square. However, the spreadsheet is programmed to permit different values for dx and dy. Because of the symmetry in this problem, only one quadrant of the system is modeled. The upper and left-hand boundary are the solid walls, where a zero-velocity boundary condition is imposed. The lower and right-hand boundaries are symmetry boundaries, where special momentum balance equations are developed to represent the symmetry. As illustrated, there is an 12 x 12 node network corresponding to a 10 x 10 interior system of control volumes (illustrated as shaded boxes). The velocity at the nodes represents the average value of the velocity in the surrounding control volume. There are half-size control volumes along the boundaries, with the corresponding velocities represented by the boundary values. There is a quarter-size control volume in the lower-left-hand corner. Fig. D.5 The mesh network to solve the momentum equation for the axial velocity distribution in a rectangular channel. As illustrated, the control volumes are square. However, the spreadsheet is programmed to permit different values for dx and dy. Because of the symmetry in this problem, only one quadrant of the system is modeled. The upper and left-hand boundary are the solid walls, where a zero-velocity boundary condition is imposed. The lower and right-hand boundaries are symmetry boundaries, where special momentum balance equations are developed to represent the symmetry. As illustrated, there is an 12 x 12 node network corresponding to a 10 x 10 interior system of control volumes (illustrated as shaded boxes). The velocity at the nodes represents the average value of the velocity in the surrounding control volume. There are half-size control volumes along the boundaries, with the corresponding velocities represented by the boundary values. There is a quarter-size control volume in the lower-left-hand corner.
Figure 4. A translating spinning cylinder. The polar vector in the rotation-translation (screw displacement) corresponds to the direction of translation and the axial vector to the direction of spin. Time reversal (7) does not change the sense of chirality of homomorphous systems (a) and (b) in terms of the helicity generated by the product of the two vectors, (a) and (b) are both right-handed. Space inversion (P) of (a) yields a left-handed system (c), the enantiomorph of (a). Time reversal of (a), followed by rotation of (b) by 180° (Rn) about an axis perpendicular to the cylindrical axis, yields (d), a homomorph of (a). Space inversion of (d) brings us back to (c). Figure 4. A translating spinning cylinder. The polar vector in the rotation-translation (screw displacement) corresponds to the direction of translation and the axial vector to the direction of spin. Time reversal (7) does not change the sense of chirality of homomorphous systems (a) and (b) in terms of the helicity generated by the product of the two vectors, (a) and (b) are both right-handed. Space inversion (P) of (a) yields a left-handed system (c), the enantiomorph of (a). Time reversal of (a), followed by rotation of (b) by 180° (Rn) about an axis perpendicular to the cylindrical axis, yields (d), a homomorph of (a). Space inversion of (d) brings us back to (c).
Where t is time, z are the axial position in the column, qt is the concentration of solute i in the stationary phase in equilibrium with Cu the mobile phase concentration of solute /, u is the mobile phase velocity, Da is the apparent dispersion coefficient, and F is the phase ratio (Vs/Vm). The equation describes that the difference between the amounts of component / that enters a slice of the column and the amount of the same component that leaves it is equal to the amount accumulated in the slice. The fist two terms on the left-hand side of Eq. 10 are the accumulation terms in the mobile and stationary phase, respectively [109], The third term is the convective term and the term on the right-hand side of Eq. 10 is the diffusion term. For a multi component system there are as many mass balance equation, as there are active components in the system [13],... [Pg.52]

The first two terms and the last term represent accumulation of energy in the fluid, the particle, and the column wall. The third term is convection of energy while the fourth term is the axial dispersion of energy. The fifth term (first term on right hand side) represents the heat transfer from the column walls. Because industrial scale systems have a small ratio of wall area to column volume, the fifth term is often negligible (the column is adiabatic), and the sixth term is often negligible because the mass of the column wall is small compared to the mass of adsorbent. [Pg.859]

Figures 19a-c show the results of a numerical simulation by a finite difference method for a 2-dimensional axially symmetric viscous fluid system. The left-hand and right-hand part of each picture show the stream lines of the melt and isotherms, respectively, within the right-hand halves of the vertical section of the crucible (see also Seeflelberg et al. 1997b). Convection below the crystal is induced by the crystal rotation and the natural convection near the crucible wall. As the crystal rotation rate and/or the crystal diameter increases, the forced convection becomes stronger and the meeting point of the forced and the natural convections near the melt surface moves from the crystal to the crucible wall. The isotherms are coupled strongly to the convection, and the temperature at the crystal growth interface increases with the acceleration of forced convection (increasing the crystal rotation rate) as well as with increasing the size of the crystal. Figures 19a-c show the results of a numerical simulation by a finite difference method for a 2-dimensional axially symmetric viscous fluid system. The left-hand and right-hand part of each picture show the stream lines of the melt and isotherms, respectively, within the right-hand halves of the vertical section of the crucible (see also Seeflelberg et al. 1997b). Convection below the crystal is induced by the crystal rotation and the natural convection near the crucible wall. As the crystal rotation rate and/or the crystal diameter increases, the forced convection becomes stronger and the meeting point of the forced and the natural convections near the melt surface moves from the crystal to the crucible wall. The isotherms are coupled strongly to the convection, and the temperature at the crystal growth interface increases with the acceleration of forced convection (increasing the crystal rotation rate) as well as with increasing the size of the crystal.
It is important to emphasize at this point that the expression for the rotation w.r.t. the y-axis requires a negative sign as a result of the assumption that translations are positive in the sense of the Cartesian coordinates and also the respect of the right-hand mle for the coordinate system. By superposing the spectral solutions for abeam element under axial, flexural, and torsion deformations, the displacement solution vector is given by ... [Pg.3381]


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Axial system

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