Laser light scattering particle size

The development and refinement of population balance techniques for the description of the behavior of laboratory and industrial crystallizers led to the belief that with accurate values for the crystal growth and nucleation kinetics, a simple MSMPR type crystallizer could be accurately modelled in terms of its CSD. Unfortunately, accurate measurement of the CSD with laser light scattering particle size analyzers (especially of the small particles) has revealed that this is not true. In mar cases the CSD data obtained from steady state operation of a MSMPR crystallizer is not a straight line as expected but curves upward (1. 32. 33V This indicates more small particles than predicted... 

D-4464 Particle Size Distribution of Catalytic Material by Laser Light Scattering Particle size distribution of catalyst particles (20 to equivalent spherical diameter) as ascertained by laser scattering 150/im light... 

MCC was prepared by hydrolysing waste cotton fabric with hydrochloric acid. The MCC was characterized by measurement of laser light scattering particle size, WAXS morphology, SEM and thermogravimetric properties. 

Pig. 9. Particle size distribution of rubber particles purified from guayule stem bark and Hevea latex. Measurements were made on rubber particles in aqueous suspension using a Horiba LA-900 Laser Light Scattering Particle Size Distribution Analyzer. —O—, Hevea — —, Guasnile. Data from Ref 12. 

Particle sizing via laser light scattering has become very popular due to its simplicity of operation (Figure 1.11). 

Different methods are available for the determination of the particle-size distribution of powdered solids [30]. These are optical microscopy (usually combined with image analysis), sieve analysis, laser light scattering of suspended particles, and electrical zone sensing. 

The vesicle size is an important parameter not only for in-process control but particularly in quality assurance, because the physical stability of the vesicle dispersion depends on particle size and particle size distribution. An appropriate and particularly quick method is laser light scattering or diffraction. Laser light diffraction can be applied to particles > 1 pm and refers to the proportionality between the intensity of diffraction and the square of the particle diameter according to the diffraction theory of Fraunhofer. 

Unfortunately, these indices are difficult to determine. Furthermore, most vesicle dispersions contain a dispersed mesophase with particle sizes below 200 nm up to 1 pm. Therefore photon correlation spectroscopy (PCS), on the basis of laser light scattering, provides an appropriate method of investigation [18]. 

Light scattering Modem laser light scattering instruments are very advanced devices for particle size distribution analyses. The laser light is scattered by the small dispersed particles or drops. The latter is known to be dependent on the radius of the particle. 

For broader size distributions and dispersions that contain a considerable amount of particles in the upper nanometer and/or the micrometer range, laser light scattering... 

Laser diffraction Interaction of a laser beam with particles and detection of the scattered light X Particle size determination... 

A variety of instruments and techniques exist for monitoring particle size. The most widely used techniques rely on laser light scattering, as reviewed by Tadros et al. (2004). Instruments manufacturers include Nicomp, Coulter, Horiba, Sympatec, and Malvern. Electron microscopy has also been used, but artifacts introduced by Lxing techniques should be carefully controlled. Typically, emulsions produced by the methods described above yield particle sizes of 100-1000 nm particle sizes less than 200 nm are generally required for emulsions used intravenously. 

Combination of static and dynamic laser light scattering is also useful to determine not only the size distribution but also the particle structure of polymer colloids such as the adsorbed surfactant layer thickness [73] and the formation of nanoparticles [74,75]. A recently developed method of determining the density of polymer particles is outlined below to illustrate the usefulness of laser light scattering as a powerful analytical tool for investigating more sophisticated colloidal problems [76-78]. 

Chang, K., Litt, M., and Jamieson, A. M., "The Measurement of Latex Particle Size by Quasielastic Laser Light Scatter-ing", J. Poly. Sci.-Phys., to be published. 

A laser light scattering method was used to characterize the particle size distribution of agglomerates and primary particles of Drug A using 0 and 30 s sonication times, respectively. As shown in Fig. 6.4, agglomerates are detectable when tested... 

The current status of prediction and modelling in the area of fuel spray combustion requires, among other parameters, the measurement of droplet or solid particle size distribution and the relative velocity between the fuel and the surrounding gas. Many optical techniques, based on laser light scattering, have been investigated to this purpose (Refs.1,2,2,]+,, 6 and j), but the only system able to simultaneously determine the size and the velocity is the dual-beam laser Doppler velocimeter shown in Figure 1. 

In colloidal suspensions of anisotropic particles, the static structure factor plays a prominent role in particle size analysis. We have used transient electric birefringence (TEB) and electron microscopy, in addition to laser light scattering, to correlate our analysis of particle size distributions of bentonite suspensions. The complementary nature of TEB and photon correlation spectroscopy (PCS) in particle size analysis will be discussed. 

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