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Coordinates laboratory

The effect known either as electroosmosis or electroendosmosis is a complement to that of electrophoresis. In the latter case, when a field F is applied, the surface or particle is mobile and moves relative to the solvent, which is fixed (in laboratory coordinates). If, however, the surface is fixed, it is the mobile diffuse layer that moves under an applied field, carrying solution with it. If one has a tube of radius r whose walls possess a certain potential and charge density, then Eqs. V-35 and V-36 again apply, with v now being the velocity of the diffuse layer. For water at 25°C, a field of about 1500 V/cm is needed to produce a velocity of 1 cm/sec if f is 100 mV (see Problem V-14). [Pg.185]

A = /W//Wp, P is impact parameter and Tq is the distance of closest approach (apsis) of the collision pair. The transformations from the CM coordinates (scattering angle y) to the laboratory coordinates with the scattering angle 0 for the primary particle and (]) for the recoiled surface atoms Is given by... [Pg.1809]

In a crossed-beam experiment the angular and velocity distributions are measured in the laboratory coordinate system, while scattering events are most conveniently described in a reference frame moving with the velocity of the centre-of-mass of the system. It is thus necessary to transfonn the measured velocity flux contour maps into the center-of-mass coordmate (CM) system [13]. Figure B2.3.2 illustrates the reagent and product velocities in the laboratory and CM coordinate systems. The CM coordinate system is travelling at the velocity c of the centre of mass... [Pg.2063]

Maximum information is obtained by making Raman measurements on oriented, transparent single crystals. The essentials of the experiment are sketched in Figure 3. The crystal is aligned with the crystallographic axes parallel to a laboratory coordinate system defined by the directions of the laser beam and the scattered beam. A useful shorthand for describing the orientational relations (the Porto notation) is illustrated in Figure 3 as z(xz) y. The first symbol is the direction of the laser beam the second symbol is the polarization direction of the laser beam the third symbol is the polarization direction of the scattered beam and the fourth symbol is the direction of the scattered beam, all with respect to the laboratory coordinate system. [Pg.433]

Flow velocity field determined by PIV. Lean limit flames propagating upward in a standard cylindrical tube in methane/air and propane/ air mixtures, (a) Methane/air—laboratory coordinates, (b) propane/air—laboratory coordinates, (c) methane/air—flame coordinates, and (d) propane/air—flame coordinates. [Pg.17]

When a notebook had been completed, and the external and QA reviews had been finalized, the laboratory coordinator locked the entire workbook, using a macro specifically developed for the purpose, and sent the workbook for collation into the final study report. Once locked, the workbook could not be altered without the knowledge and agreement of the laboratory staff responsible for generating and certifying its contents. Such a system is critical in order to maintain integrity of reported results. [Pg.245]

When applied to a volume-fixed frame of reference (i.e., laboratory coordinates) with ordinary concentration units (e.g., g/cm3), these equations are applicable only to nonswelling systems. The diffusion coefficient obtained for the swelling system is the polymer-solvent mutual diffusion coefficient in a volume-fixed reference frame, Dv. Also, the single diffusion coefficient extracted from this analysis will be some average of concentration-dependent values if the diffusion coefficient is not constant. [Pg.526]

The subscripts refer to Cartesian coordinates in the laboratory coordinate system. The terms E(go) and B(go) are the electric and magnetic induction fields, respectively. In addition, the nonlinear induced magnetic moment (magnetization) is defined as ... [Pg.529]

Equation (4.4), which connects the known variables, unbumed gas pressure, temperature, and density, is not an independent equation. In the coordinate system chosen, //, is (lie velocity fed into the wave and u2 is the velocity coming out of the wave. In the laboratory coordinate system, the velocity ahead of the wave is zero, the wave velocity is uh and (u — u2) is the velocity of the burned gases with respect to the tube. The unknowns in the system are U, u2, P2, T2, and p2. The chemical energy release is q, and the stagnation adiabatic combustion temperature is T, for n-> = 0. The symbols follow the normal convention. [Pg.148]

In place of subscripts b, u, and o, some authors use 3, 2, and 1, respectively. The velocities (v) and (pr) are both expressed relative to the walls and to the quiescent gas, which are stationary in "laboratory coordinates. Here (u) indicates intermediate... [Pg.250]

Detonation Waves, Stationary, Stand -ing-, or Stabilized. Under these terms are known waves which remain stationary relative to laboratory coordinates According to Nicholls et al (Refs 63,... [Pg.700]

Fig 1 Steady plane shock front propagating into undisturbed materials in laboratory coordinates ... [Pg.179]

Routine or field laboratories involved in the ANP are controlled in each Member State by at least one National Reference Laboratory (NRL) designated by the National Government (51, 52). National Laboratories are in turn responsible for the standards maintained in any other laboratories in their own country that are involved in the National Sampling Plan program. National Reference laboratories coordinate standards and methods of analysis for each group of residues, and may undertake work on all or limited classes of the veterinary drug areas listed in Directive 86/469/EEC. [Pg.375]

A sufficiently rarefied gas, or a mixture of gases, consists of a number of neutral molecules of species 1 and 2 (which may or may not be the same). We may assume a distribution of velocities (measured in the laboratory frame), fi ( ) d3u, that may be modeled by a Maxwellian distribution function, with i = 1 or 2, as long as the duration of the average collision is short compared to the time between collisions. For binary collisions, one usually transforms from laboratory coordinates, Vj, to relative ( >12) and center-of-mass (1>cm) velocities,... [Pg.29]

Restriction (i) implies that history of the system is not a relevant thermodynamic property. Restriction (ii) implies that position or orientation of the system are not considered thermodynamic properties, because different observers must be free to select their own preferred laboratory coordinate systems. (Note that omission of position r as a relevant property strongly distinguishes thermodynamics from classical dynamics, where spatial location r of the center of mass is a prominent variable of the system.)... [Pg.62]

The state of stress in a flowing liquid is assumed to be describable in the same way as in a solid, viz. by means of a stress-ellipsoid. As is well-known, the axes of this ellipsoid coincide with directions perpendicular to special material planes on which no shear stresses act. From this characterization it follows that e.g. the direction perpendicular to the shearing planes cannot coincide with one of the axes of the stress-ellipsoid. A laboratory coordinate system is chosen, as shown in Fig. 1.1. The x- (or 1-) direction is chosen parallel with the stream lines, the y- (or 2-) direction perpendicular to the shearing planes. The third direction (z- or 3-direction) completes a right-handed Cartesian coordinate system. Only this third (or neutral) direction coincides with one of the principal axes of stress, as in a plane perpendicular to this axis no shear stress is applied. Although the other two principal axes do not coincide with the x- and y-directions, they must lie in the same plane which is sometimes called the plane of flow, or the 1—2 plane. As a consequence, the transformation of tensor components from the principal axes to the axes of the laboratory system becomes a simple two-dimensional one. When the first principal axis is... [Pg.173]

Fig. 1.1. Laboratory coordinate system x direction of flow (also 1-direction), y direction of velocity gradient (also 2-direction), I, II principal directions of stress, y orientation angle if stress-ellipsoid, vx velocity (in -direction), q velocity gradient... Fig. 1.1. Laboratory coordinate system x direction of flow (also 1-direction), y direction of velocity gradient (also 2-direction), I, II principal directions of stress, y orientation angle if stress-ellipsoid, vx velocity (in -direction), q velocity gradient...
In this equation is the internal friction factor of thej-th normal mode and Qjj1 is the inverse transformation matrix of Zimm. In other words, Cerf assumed that one can ascribe a separate internal friction factor to every normal mode. This assumption is critisized by Budtov and Gotlib (183) as, in this way, the elements of the internal friction matrix in the laboratory coordinate system x, y, z, viz. [Pg.281]

Solution. The laboratory coordinate system is used and there is no change in the overall specimen volume. The integral in Eq. 4.50 is proportional to the sum area 1 + area 2 in Fig. 4.7. Area 1 is positive and area 2 is negative. When x = 0 is set at the position of the original interface, area 2 is proportional to the amount of diffusant that has left... [Pg.91]

Fig. 13. Flow field before the flame front in the laboratory coordinate system. (Region 1—potential flow, region 2—vortex flow, region 3—stagnation zone, region 4—channel wall). Fig. 13. Flow field before the flame front in the laboratory coordinate system. (Region 1—potential flow, region 2—vortex flow, region 3—stagnation zone, region 4—channel wall).
Whereas the group jr and its representations are relevant and sufficient for problems which are completely defined by relative nuclear configurations (RNCs) of a SRM, primitive period isometric transformations have to be considered as nontrivial symmetry operations in all those applications where the orientation of the NC w.r.t. the frame and laboratory coordinate system is relevant, e.g. the rotation-internal motion energy eigenvalue problem of a SRM. Inclusion of such primitive period operations leads to the internal isometric group ( ) represented faithfully by... [Pg.15]

The index 1 indicates that this representation refers to the position vectors expressed in the laboratory coordinate system. The last equation may be commented upon as follows ... [Pg.24]

Fig. 51.2. An experimental approach curve for a 25 pm diameter Pt UME towards glass. The illustration shows the distance d0 — Offset — Zq between the active electrode surface and the sample in the moment of the mechanical touch by the insulating sheath. The z arrow illustrates the relation to the laboratory coordinate system in which the movement of the UME is measured, z — 0 corresponds to the start point of the approach curve, z0 is the coordinate of the active electrode area, when the insulating sheath touches the surface, zoffset is the coordinate of the surface. Note The tilt of the UME is greatly exaggerated in order to illustrate the principle, while the radius of the glass sheath is smaller in the sketch a real experiment RG = 10. The theoretical curve (solid line) was calculated according to Eq. (1) with the following coordinate transformations z = -rTL+z0ffset rT = 12.84 pm, zoffi5et = 201.52 pm, iT = iT>o0 = 5.554 nA. Fig. 51.2. An experimental approach curve for a 25 pm diameter Pt UME towards glass. The illustration shows the distance d0 — Offset — Zq between the active electrode surface and the sample in the moment of the mechanical touch by the insulating sheath. The z arrow illustrates the relation to the laboratory coordinate system in which the movement of the UME is measured, z — 0 corresponds to the start point of the approach curve, z0 is the coordinate of the active electrode area, when the insulating sheath touches the surface, zoffset is the coordinate of the surface. Note The tilt of the UME is greatly exaggerated in order to illustrate the principle, while the radius of the glass sheath is smaller in the sketch a real experiment RG = 10. The theoretical curve (solid line) was calculated according to Eq. (1) with the following coordinate transformations z = -rTL+z0ffset rT = 12.84 pm, zoffi5et = 201.52 pm, iT = iT>o0 = 5.554 nA.
The quadmpoie operator transforms as WY V and makes the 1 s —> 3d transition electric quadmpoie allowed when the dY v2 orbital (in molecular coordinates) bisects the k and E vectors (which define the laboratory coordinates). Quadmpoie intensity is usually very low however, at —9000 eV the wavelength of light is — 1.4 A and in this case the long-wave approximation no longer holds and higher terms in the multipole expansion in Equation 1.2 become important. [Pg.25]


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