Mies theory

The abihty of fillers to improve paper brightness increases with their intrinsic brightness, surface area, and refractive index. According to the Mie theory, this abiUty is maximum at an optimum filler particle size, about 0.25 pm in most cases, where the filler particle size is roughly one-half the wavelength of light used for the observation. 

Other measurements important to visual air quality are pollutant related, i.e., the size distribution, mass concentration, and number concentration of airborne particles and their chemical composition. From the size distribution, the Mie theory of light scattering can be used to calculate the scattering coefficient (20). Table 14-2 summarizes the different types of visual monitoring methods (21). 

MIE Theory a complex mathematical model that allows the computation of the amount of energy (light) scattered by spherical particles. 

Table I compares the measured values of extinction coefficients with the values calculated from theory at wavelengths of 25U, 280 and 350 nm. The lower values of extinction coefficients for the larger particles measured, using the online detector compared to the Beckman instrument, are due to the optical effects discussed above. The disagreement between the extinction coefficients calculated from Mie theory for non-absorbing spheres and the measured values from the Beckman instrument is very significant, particularly at 2 k and 280 nm.

Row 1. Uncorrected diameter averaged from Mie theory (Equation 13). Row 2. Diameter averages in row 1 corrected using Rayleigh correction factors (Equation 15). 

Row 2. Cadculated from diameter averages for each component as given by Mie Theory. For e.g. 

The diameter averages of the mixtures evaluated using Mie Theory are presented in Table VII. For each mixture they are computed for 0 values equal to those of individual components and their mean. The averages fortunately are not very sensitive to the values between those of individual components. Computed values with mean for each mixture compare very favourably with third row entries for each mixture in Table VI. Similar results were obtained when Raylei scattering was considered. 

Hollow gold spheres or core-shell particles consisting of a gold shell on a core of some other material have recently attracted attention. This is because they have interesting and tunable optical extinction properties [56]. These can be readily calculated using Mie theory [57], and there had been some scattered early interest in these shapes as a result [58, 59], but the versatility and properties of these particles only became widely... 

Linear Absorption of Embedded Metal Clusters The Mie Theory... 

The TEM data have been used to simulate, in the frame of the Mie theory and Maxwell-Garnett effective medium approximation [15], the optical absorption spectra of the sample implanted with 5 x lO Au /cm. The results are reported in Figure 8(c). In the first model used to describe... 

Figure 9. Comparison between a simulation based on the Mie theory of OD in the UV-Vis range for 3 nm clusters of pure Au, Ag, and Auo.4Ago.6 alloy in silica (a), with the experimental OD of the same systems in ion-implanted silica (b). (Reprinted from Ref [1], 2005, with permission from Italian Physical Society).

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