Scattering maximum

The smaller the particle size, the lower the wavelength at which maximum scattering occurs. Thus, ultrafine (20-50nm) T1O2 is used as a UV filter in skin care and cosmetic products. (Sec V. P. S. Jl din, Chem. Br. 29, 503-5 (1993).)... 

Exposure Time Perform some test exposures and choose an exposure time so that the maximum scattering originating from the sample results in about 10,000 counts in some of the relevant pixels. Is the maximum lower than 2000 counts, a quantitative analysis will be very difficult. 

Figure 2. Time required for maximum scattering to return to...

As a pigment, each iron oxide has an optimum particle size which is that with the maximum scattering cross section. This optimum particle size is lower, the higher the refractive index of the mineral. For hematite, the size corresponding to the maximum in scattering/absorption cross section is ca. 1 pm. As the particle size decreases, the relative scattering cross section drops to zero and the relative absorption cross section levels out. As a result, very small particles of hematite are transparent. 

The scattered light intensity change of 25 wt% PEI blend during curing at 150°C is shown in Figure 3.12. For the initial stage of phase separation, the maximum scattered intensity... 

The refractive index n of ZnS, which determines its scattering properties, is 2.37 and is much greater than that of plastics and binders (n = 1.5-1.6). Spheroidal ZnS particles have their maximum scattering power at a diameter of 294 nm. Barium sulfate does not directly contribute to the light scattering due to its relatively low refractive index (n = 1.64), but acts as an extender, and increases the scattering efficiency of the ZnS. 

For both samples, maximum scattering is observed in the external zone of the fibers, indicating a higher concentration of pores in this outer zone, as the activation process proceeds. In addition, it can be observed that the PI profiles are different for the C02 and steam-activated materials. In the case of steam, the scattering from all the internal zones is very similar and much lower than... 

This trend observed for chemically activated carbon fibers is very different from that obtained for the ACF prepared by physical activation of the same raw carbon fiber with C02 and steam, where the maximum scattering appears at the external zone of the fiber (see Figure 4.19). In the case of NaOH and KOH activation, the results indicate that the activating agents penetrate the fiber, which is a new interesting observation, which points out that alkaline hydroxides penetrate much better than C02 and steam. The different evolution of porosity obtained for the chemically activated carbon fibers compared to the physically activated carbon fibers could be explained considering the important differences between the mechanisms of both the activation methods. 

On the basis of the cluster dynamics, BS theory predicted the time evolution of the cluster size r(t) has the same form as Equation 7 and the maximum scattered intensity Im(t) assumes a similar power law relation, i.e.. 

Aqueous hydroxypropyl cellulose solutions amplification vs. wave number, 275,277/ apparent diffusivity vs. temperature, 275,277/ calculation of maximum scattered intensity, 278... 

The optimal thickness of the sample for maximum scattering intensity in a transmission experiment is l/ x. As the scattering intensity follows d/exp (pd) 82 % of the maximum scattering intensity are reached at half the optimal thickness defined above. There may be two reasons which favour thin samples ... 

Fig. 20. The domains in which X-ray resonance scattering and EXAFS provide structural information. Structural resolution from diffraction is assumed to be limited by the maximum scattering angle of 60° and the wavelength range from 0.8 to 7.4 A. This compares to the specifications of the instrument given in Fig. 8...

Figure 9.5 Schematic illustration of the phase-separation process after a temperature quench into the spinodal region of the phase diagram. The time dependence of the temperature quench from the spinodal temperature to some final temperature Tfinai is shown in the top diagram. This quench time can be made arbitrarily fast, in which case it has no effect on the time period over which the linear or other regimes persist. The bottom diagram shows the maximum-scattering wavevector qm of the spinodal pattern as a function of time t, with qm oc r . At first, in the linear regime, qm is constant, so that a = 0 but as the pattern coarsens, qm decreases, initially as qm oc due to diffusive Ostwald ripening. Later, when the interfaces are well defined, if the morphology is bicontinuous, there is a crossover to a fast hydrodynamic regime with q , oct. (From Tanaka 1995, reprinted with permission from the American Physical Society.)...

Pc q q qm r t t fraction of allowed bonds at percolation transition (Chapter 5) electric charge scattering vector wavenumber at maximum scattering intensity distance of center-of-mass separation time past time... 

Maximum scattering occurs when the droplet size is on the order of the wavelength of light. The liquid crystal droplet size is altered by warming the films to form a homogeneous solution, followed by cooling at a controlled rate. Table II lists droplet size as a function of cooling... 

Exposure Time Perform some test exposures and choose an exposure time so that the maximum scattering originating from the sample results in about... 

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