Momentum Monodisperse

There are several bottom-up methods for the preparation of nanoparticles and also colloidal nanometals. Amongst these, the salt-reduction method is one of the most powerful in obtaining monodisperse colloidal particles. Electrochemical methods, which gained prominence recently after the days of Faraday, are not used to prepare colloidal nanoparticles on a large scale [26, 46], The decomposition of lower valent transitional metal complexes is gaining momentum in recent years for the production of uniform particle size nanoparticles in multigram amounts [47,48],... 

The MMAD and GSD of aerosols are therefore critical factors in determining the deposition patterns within the lung. Aerosols with larger MMADs will deposit higher in the respiratory tract since the aerosol particles will have greater momentum. A polydisperse aerosol is also likely to show greater deposition in the TB region than a monodisperse aerosol of the same MMAD. 

Hydrodynamic mechanisms are those which produce particle interactions through the surrounding fluid due to hydrodynamic forces and the asymmetry of the flow field around each particle. These mechanisms, which are not dependent on the relative differences in acoustic particle entrainments, can act from distances larger than the acoustic displacement and have to be considered as the main mechanism in the agglomeration of monodispersed aerosols, where particles are equally entrained. There are two main types of hydrodynamic mechanisms, namely mutual radiation pressure [50] and the acoustic wake effect [51,52]. The radiation pressure is a second-order effect which produces a force on a particle immersed in an acoustic field due to the transfer of momentum from the acoustic wave to the particle. This force moves the particles towards the pressure node or antinode planes of the applied standing wave, depending on the size and density of the particles. The mutual radial pressure can be computed from the primary wave as well as from other wave fields of nearby scatters. In fact, it gives rise to particle interactions as the result of forces produced on two adjacent particles by a non-linear combination of incident and scattered waves. 

Nigmatulin RI, Lahey RT Jr, Drew DA (1996) On the Different Forms of Momentum Equations and on the Intra- and Interphase Interaction in the Hydromechanics of a Monodispersed Mixture. Chem Eng Comm 141-142 287-302... 

As a second example, we consider the kinetic equation (KE) for monodisperse, isothermal solid particles suspended in a constant-density gas phase. For clarity, we assume that the particle material density is significantly larger than that of the gas so that only the fluid drag and buoyancy terms are needed to account for momentum exchange between the two phases (Maxey Riley, 1983). In this example, the particles are large enough to have finite inertia and thus they evolve with a velocity that can be quite different than that of the gas phase. 

Monodisperse hard-sphere collisions In addition, conservation of momentum implies that... 

An alternative approach makes use of two-phase flow momentum conservation equations. Doubtless, such an approach forms a more sound foundation for the theoretical study of polydisperse and, in particular, binary fluidization. In principle, this approach may be based on the same notions and concepts as the fluid dynamic theory of monodisperse coarse suspensions developed in the present article. However, a number of new problems arise which are specific for polydisperse particulate mixtures. Among these new problems are ... 

The particle beam interface (Fig. 6) was created under the acronym MAGIC (monodisperse aerosol generator interface for chromatography) [28]. Now, the aerosol is produced by a variety of means (with auxiliary gas, thermospray, or ultrasonic nebulizers) at atmospheric pressure and a uniform distribution of the droplets results in particles of a narrow size distribution, which can be handled more efficiently by the separator. The droplets are dried to particles in a heated expansion chamber, and a momentum separator isolates the particles from the gas. In the source, the particles are destroyed by impact and the sample is released and ionized by using El, Cl, or even FAB. The appearance of the El spectra is almost identical to conventional El spectra obtained by direct probe or GC/MS. Therefore, library searches are possible, which is the major advantage of this interface. 

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