Optically equivalent size

Optical media have the capacity to handle much larger amounts of digitized information than equivalent sizes of magnetic media. These capacities... 

The optical properties of heterogeneous materials are of considerable interest in atmospheric science, astronomy and optical particle sizing. Random dispersions of inclusions in a homogeneous host medium can be equivalently considered as effectively homogeneous after using various homogenization formalisms [36,210]. The effective permittivity of a heterogeneous material relates... 

Wlrile tire Bms fonnula can be used to locate tire spectral position of tire excitonic state, tliere is no equivalent a priori description of the spectral widtli of tliis state. These bandwidtlis have been attributed to a combination of effects, including inlromogeneous broadening arising from size dispersion, optical dephasing from exciton-surface and exciton-phonon scattering, and fast lifetimes resulting from surface localization 1167, 168, 170, 1711. Due to tire complex nature of tliese line shapes, tliere have been few quantitative calculations of absorjDtion spectra. This situation is in contrast witli tliat of metal nanoparticles, where a more quantitative level of prediction is possible. 

Many inert pigments (often known as fillers) are incorporated into paper in addition to the cellulosic fibres. They may be added to improve certain optical properties—in particular opacity and brightness—or simply as a cheap replacement for costly fibre. The two most common pigments are kaolin (china clay) and chalk (limestone), but talc and speciality pigments such as titanium dioxide are also used. The particle size for general purpose fillers is normally expressed as an equivalent spherical diameter (esd) and this is determined from sedimentation data. Values for the common paper-... 

The case of a bead in a trap is also equivalent to the power fluctuations in a resistance in an RC electrical circuit [65] (see Fig. 4). The experimental setup is shown in Fig. 5. A micron-sized bead is immersed in water and trapped in an optical well. In the simplest case the trapping potential is harmonic. Flere we will assume that the potential well can have an arbitrary shape and carry out specific analytical computations for the harmonic case. 

One serious limitation of NMR measurements is the size of sample required. It is not possible to measure trace amounts or extremely dilute solutions as is possible in optical spectroscopy. When there is but a single proton in a compound to be measured, we have been able to use concentrations down to one mole per cent, and correspondingly lower concentrations if more than one equivalent proton is present. Gaseous samples, with the possible exception of such gases as methane, ethylene, benzene, etc., having several equivalent protons, usually require pressures in excess of one atmosphere. 

Laser Microminiaturization—Target Optical Computer. For many years, scientists have accepted the fact that optical computers would not become a reality until optical components of micro size and exceptional performance equivalent to the already existing electronic switches and circuits could be developed. Thus, the optical compuicr became a major driving force toward the development of optical component. The problem was extraordinarily complex because size reductions of several orders of magnitude were mandalory. 

The output of the disk centrifuge, a curve of optical density versus time, can be converted to a particle size distribution by using Stokes law to convert the time axis to a size axis and by the application of light-scattering theory to calculate the particle frequencies from the optical densities. As described herein, one obtains mass distributions with linear size increments or the equivalent area distributions with logarithmic increments. 

From a comparison of the optical absorption and excitation data for the oxides (Table V), it is clear that the energy decreases with increasing cation size along the series Mg to Ba. The bulk exciton transitions of these oxides also decrease in a similar manner (Table VI). It is possible to make a semi-quantitative calculation of the intrinsic surface energy states using the approach of Levine and Mark (151) where the ions in an ideal surface are considered to be equivalent to bulk ions except for their reduced Madelung... 

Fig. 1. Model calculations of the temporal dependence of the vertical optical thickness of a nuclear dust cloud, averaged over the Northern Hemisphere (X = 550 nm). The mass concentration of dust particles in the cloud corresponds to the injection to the atmosphere of 3.3 X 10 (1), 1 X 10 (2), and 1 X 10 (3) tons of particulate matter per Mt of an equivalent charge. Particles size distribution is log-normal and parameterized by the power law (see the text) 4,5 — calculations on the assumption of the prevailing content in the cloud of large (r , = 1.0 pm) and small (r , = 0.1 pm) particles.

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