Propagation direction

Some of the problems often encountered during ultrasonic inspection of plane specimens are also found on cylindrical specimens. For example, problems associated with the directional characteristic of the ultrasonic transducer. Furthermore, the discontinuity influences the shape and propagation direction of a reflected pulse, causing wave mode transformation. In addition, the specimen influences the shape and amplitude of the reflected pulse by sound absorption. 

The last attribute of tire electromagnetic field we need to discuss is wave polarization. The nature of tire transverse field is such tliat tire oscillating field disturbance (which is perjDendicular to tire propagation direction) has a particular orientation in space. The polarization of light is detennined by tire time evolution of tire direction of tire electric field... 

The gauge element in the form of a foil (50 ohms) is normally embedded in materials such that the active gauge element is normal to the stress-wave propagation direction. Manganin is the only in situ stress gauge available for... 

Figure 4.11. Diagrammatic sketches of atomic lattice rearrangements as a result of dynamic compression, which give rise to (a) elastic shock, (b) deformational shock, and (c) shock-induced phase change. In the case of an elastic shock in an isotropic medium, the lateral stress is a factor v/(l — v) less than the stress in the shock propagation direction. Here v is Poisson s ratio. In cases (b) and (c) stresses are assumed equal in all directions if the shock stress amplitude is much greater than the material strength.

In the following development we consider a plane wave of infinite lateral extent traveling in the positive Xj direction (the wave front itself lies in the Xj, Xj plane). When discussing anisotropic materials we restrict discussion to those propagation directions which produce longitudinal particle motion only i.e., if u is the particle velocity, then Uj = Uj = 0. The <100>, <110>, and <111 > direction in cubic crystals have this property, for example. The derivations presented here are heuristic with emphasis on the essential qualitative features of plastic flow. References are provided for those interested in proper quantitative features of crystal anisotropy and nonlinear thermoelasticity. 

When the vector components are not in phase with each other, the projection of the tip of the electric vector onto a plane perpendicular to the beam propagation direction traces out an ellipse, as shown in Figure 2b. 

The flame propagation direction affects the type of flame arrester selected. An end-of-line or in-line deflagration flame arrester used for the protection of an individual tank may be of a unidirectional design because the flame will only propagate from the atmosphere towards the tank interior. A bidirectional flame arrester design, however, is needed for an in-line application in a vapor recovery (vent manifold) system because the vapors must be able to flow from the tank interior into the manifold, or from the manifold into the tank interior. Consequently, flame may propagate in either direction. 

Fluorescence was collected perpendicular to the laser beam propagation direction (i.e. 90 degree light collection) using... 

Figure 4-1. Light as transverse electric ( ) and magnetic (5) oscillating fields normal to the propagation direction.

Numerical simulation of a spirming detonation in Hj/air mixture in a circular tube at various times. Gray and green space isosurfaces in pressure are the detonation front and the pressure of 6 MPa. White arrow propagating direction of the detonation front, pink arrow rotating direction of the transverse detonation. TD—transverse detonation, and LT—long pressure trail. (Reprinted from Tsuboi, N., Eto, K., and Hayashi, A.K., Combust. Flame, 149,144,2007. With permission.)... 

In CDAD, a chiral experimental geometry is created about a fixed molecular orientation, and the asymmetry in the electron distribution can be observed in directions mutually perpendicular to the photon propagation direction and the... 

Figure 10.2 Graded co-continuous morphology obtained at different depths along the propagation direction of light in a PSAF/MMA (10/90) blend irradiated with 365 nm UV light at room temperature. The number on the upper left in each figure indicates the Z-coordinates of the sample.

Apart from the separation into two fractions, the propagator can also be interpreted in terms of an average quantity, the second moment of displacements, which is proportional to the dispersion coefficient D (A). Rather than computing D ( A) from the shape of the propagator directly, it is also possible to obtain it from the initial slope of the signal function E(q,A) in a ID NMR experiment [43] ... 

The first and third order terms in odd powers of the applied electric field are present for all materials. In the second order term, a polarization is induced proportional to the square of the applied electric field, and the. nonlinear second order optical susceptibility must, therefore, vanish in crystals that possess a center of symmetry. In addition to the noncentrosymmetric structure, efficient second harmonic generation requires crystals to possess propagation directions where the crystal birefringence cancels the natural dispersion leading to phase matching. 

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