Natural charging electrostatic charges

The electrostatic force is directly proportional to the net charge of an aerosol particle. Therefore, effective charging of the particles is of great importance. Airborne particles are normally charged either due to their birth processes or due to charge transfer from gas ions to particles. The natural charging of particles is normally so weak that it has no practical importance for electrostatic air cleaning. 

Because of the unavoidable tendency of granular solids to become triboelectrically charged when handled, it is no surprise that electrostatic phenomena are often quite pronounced in fluidized and spouted beds. The vigorous motion of fluidized particles—with constant particle-particle and particle-wall contacts—guarantees that electrical charging will take place. Electrostatic adhesion and cohesion, observed and recorded in the very earliest experimental investigations of fluidization, were immediately identified as experimental nuisances to be overcome. Somewhat later, the hazardous nature of electrostatics came to be appreciated. 

Table 5.15 Comparing Mulliken, electrostatic potential and natural charges, and Mulliken and Lowdin bond orders, at various levels, for hydrogen fluoride. The geometry used in each case corresponds to the method/basis set for that charge or bond order, but any reasonable geometry should give essentially the same results. There are no experimental data...

Outside the QTAIM realm, the main definitions of atomic charges are Mulliken charge, electrostatic charge, and natural charge [3]. Values can differ considerably from one method to another, but the trend with a particular method can provide useful information. None of these three methods of assigning charge claims to be unique. 

Scheme 2.161 Despite the resonance stabilization of singlet difluorocarbene by T-donation (+R) (box) from the a-fluorine atom, the carbon atom still has quite a large positive natural charge qc of -1-0.84 e = -0.42 e), rendering the species moderately electrophilic (geometry optimization at the MP2/6-311 - -C level of theory, electrostatic potential mapped on electron isodensity surface blue and red denote positive and negative partial charges, respectively) [33, 34). Difluorocarbene reacts readily with electron-rich olefins to yield gem-difluorocyclopropanes.

These results showed, that the nature of electrostatic balance of positive charges (by protons or by other ions) seems to depend on the protein environment of the manganese-centre. This implied that there was no unique way to attribute released protons to reactions of water which is bound to the water oxidizing complex. 

Solutes in the mobile phase can remain in the bulk water, be associated to the free surfactant monomers or micelle siuface, be inserted into the micelle palisade layer, or penetrate into the miceUe core. The surface of the surfactant-modified stationary phase is similar to an opened micelle and can give rise to similar interactions with the solutes. With non-ionic surfactants, the interactions are mainly hydrophobic in nature. Charged heads of ionic surfactants in both micelles and monomers adsorbed on the stationary phase are in contact with the polar solution, producing additional electrostatic interactions with... 

Some Pebax grades are used to enhance the characteristics of other thermoplastics, in particular as antistatic agents, since they naturally disperse electrostatic charges, and as such can be added to a large number of thermoplastic matrices (acrylonitrile-butadiene-styrene (ABS), polystyrene, polyoxy-methylene (POM), polyvinylchloride (PVC), polymethylmethacrylate (PMMA) and polycarbonate (PC)) to impart permanent antistatic properties, whatever the ambient relative moisture or surface friction they may be subjected to. These antistatic compounds are suitable for countless applications in office and electronic equipment (photocopier components, printer components, etc.) as well as in technical packaging,... 

Strong electrostatic interaction between an ionic catalyst and an ionic snbstrate may drastically change the rate of a reaction depending on the nature of electrostatic interaction, and its predominant effects on TS or GS of the reactant in the rate-determining step. Energy of interaction (E) between two point charges may be expressed as... 

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