Vv scattering

Small-angle light scattering has also been extensively applied to PLCs subject to flow [173]. As in the case of scattering dichroism, SALS patterns arise principally from fluctuations in orientation, and these arc strongest in the vicinity of disclinations, or defects in the director field. The experimental geometries used for SALS in liquid crystals normally use polarizers placed before and after the sample. The arrangements include VV scatter-... 

For non-volume filling crystalline polymers, there is an appreciable contribution arising from the difference in scattering length of the crystalline and amorphous phases. This gives rise to a (Vv) scattering maximum during the course of crystallization. 

Figure 14. The components of the Vv scattering in Fig. 13 attributed to the moieties with coherence times xj, i (lower) and tj, 2 (upper).

The directions of the incident and scattered light are conventionally taken to define the horizontal plane, the two fundamental polarizations of linearly polarized light being chosen as the vertical (V) and horizontal (H) directions. Polarized light scattering experiments study VV scattering the incident and scattered light rays... 

The orientation of /I with respect to the scattering direction determines the scattered field s polarization, a is the molecular polarizability tensor for molecule i, and has a scalar (on-diagonal) component a, I being the identity tensor, that leads to VV scattering. Note that also may have a nonzero tensor component 5a = — al... 

Linearly polarized lights are described by i// = 0 (horizontal, H) or i/ = ttl2 (vertical, V) giving the standard HV and VV scattering geometries, respectively. 

A review article has been published on depolarized Raman spectroscopy in molten salts, and it is discussed briefly here for the case of molten nitrates. Polarized (VV) and depolarized (HV) Raman scattering of the 1050 cm" line was used. The intensity of the isotropic part of the... 

Fig. 2.49 Dynamic structure factor at two temperatures for a nearly symmetric PEP-PDMS diblock (V = 1110) determined using dynamic light scattering in the VV geometry at a fixed wavevector q = 2.5 X 10s cm-1 (Anastasiadis et al. 1993a). The inverse Laplace transform of the correlation function for the 90 °C data is shown in the inset. Three dynamic modes (cluster, heterogeneity and internal) are evident with increasing relaxation times.

In the present work with a laser source and photon counting detection we were able to make measurements at concentrations lower than the work of Heller and Tabibian where multiple scattering and particle turbidity were negligible and single scattering could be directly observed. It was possible to make direct measurements of IQ and utilize the Rayleigh ratio Vv and Mie theory coefficient (ii)A by... 

Tuchin VV. Tissue Optics Light scattering methods and instruments for medical diagnosis. SPIE Tutorial Texts in Optical Engineering. Bellingham, WA SPIE Press, 2000. 

A collision between two particles X and Y, with masses mx and my and velocities x and vv, can be reduced to the motion of a single representative point (P), with mass /t = mamj(mx + mv), moving with relative velocity v = vx — v in a potential V(r), which is a function only of the distance of P from a scattering center (O). This one-body, two-dimensional problem is represented in Figure 1.1. For a particular interaction potential, a collision... 

Figure 4. Laser scattering pattern of microtomed section parallel to the [100] direction (A) is Hv, exposure 1/10 sec and (B) is Vv, exposure 1/250 sec. The subscript denotes the polarization of the incident radiation. Sample to film distance, 11.5 cm in (A) and (B) layer beam 0.25 mm diameter.

Both the VV and HV polarizations contribute to the isotropic scattering cross section while the anisotropic and HV scattering cross sections are proportional. The intensities of the isotropic and anisotropic scattered light are given by the equations... 

Finally, M is introduced for convenience and represents the integral function of polarizability. It is the only function, the value of which depends on the polarizability characterizing the scattering medium. /iso( u) Raman spectrum depends only on the vibration motion and /aniso( y) depends on both vibration and reorientation motions of the molecule. In addition to the familiar qualitative use of the depolarization ratio, P = - Hv/. vv, to identify symmetric modes (i.e. p < 0.75), the quantitative studies of /iso and /aniso may provide detailed information about the vibration and reorientation relaxation. 

This implies that Vv(r, t) can be used to describe an exponentially decaying probability distribution. The time-independent partial wave solutions above a threshold obey scattering boundary conditions. They are thus proportional to the regular solution tpe(E, r) a origin and tend to infinity like Jost solutions f E,r) ... 

The hght scattering in both the parallel (Vv) and cross polarization (Hv) modes, was measured for PP/partiaUy hydrogenated oligo(styrene-co-indene) blends. The results indicated that the primary lamellae (thick line in Figure 8.13b) sufficiently grew in the... 

The longitudinal Brillouin spectrum appears when both the incident and scattered light are polarized vertically with respect to the scattering plane (/vv) The transverse Brillouin spectrum results when the incident polarization is perpendicular to the scattered polarization (Ihv =1vh). 

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