Tribo charging

Nomura, T. Satoh, T. Masuda, H. The environment humidity effect on the tribo-charge of powder. Powder Technol. 2003, 135-136, 43-49. 

In particular, fumed alumina and fumed silica products provide tribo-charging, free-flow, fluidization and anti-blocking in powder coating applications. Typically, fumed alumina is used for tribo coating processes and either fumed silica or hexamethyldisilazane treated fumed alumina is selected for corona coating processes (3). 

Kamer, S., Maier, M., Littringer, E. M., Urbanetz, N. A. (2014). Surface roughness effects on the tribo-charging and mixing homogeneity of adhesive mixtures used in dry powder inhalers. Powder Technology, 264,544—549. 

Electrostatic-Separation Machines The first electrostatic machines to be used commercially employed the principle of contact elec trification. These were free-fall devices incorporating large vertical plates between which an electrostatic field was maintained. Tribo-elec tric separation (contact charging) has experienced an increase in apphcations due to advances in mechanical self-cleaning and electrical design as well as the development of efficient precharging techniques. 

The Coulomb equation describes tribo-electric charging (Fc) between spherical particle and an adjacent uncharged particle ... 

In general, the data of Table 4 tend to confirm this estimated range however, the upper limit of 1.0 pC/kg is considerably exceeded in the case of data obtained with individual particles of tribo-active, insulating polymers. Whether or not significant volume separation of positive and negative charges occurs with these polymers is not known. Thus, the validity of the upper limit in Eq. (9) is difficult to judge. 

Luminescence is the emission of light at RT under the influence of various physical agents as mechanical(tribo-l), electrical (electro-1), radiant (photo-1), thermal (thermo-1), or chemical (chemo-1) means. The exciting source also may consist of moving charged particles, such as alpha-, beta-, or gamma-. Certain substances luminesce on crystallization, as,... 

FIGURE 8.1 Triboelectric series of materials. Cotton is used as the neutral or reference material. Tribo-negative materials contain free negative charges, and tribo-positive materials contain free positive charges. These charges are easily transferred to other materials that they might contact. 

Tribo electric Based on electrostatic charge environment Only for clean, dry and non-surface-treated... 

In his phenomenological study [1], Briick ordered a number of polymers in a row describing their affinity to become positively or negatively charged when rubbed with each other. Briick s row and other comparable rows first demonstrated the fundamental relationship between the chemical structure of a polymer and its tribo-electrical charging properties. In a former work [2] we followed that idea and showed that the tribo-electrical charging of two polymer species charged in a fluidized bed clearly depends on the affinity of the polymer surface to take up electron... 

The formation of charge domains showed that the fundamental electron transfer process involves a high number of surface sites. The tribo-electric charging of polymers has to be considered as a collective phenomenon. 

The tribo-electric charging of polymers is a collective phenomenon of numerous electron transfer processes in the contact zone of two colliding particles. The SPM technique allows to visualize the charge distribution on polymer surfaces. It was shown that oppositely charge domains can stably exist side by side although considerable filed strengths are present. 

Transient approach to charge equilibrium, 207-208 Transmittance, 265 Tribo electrification, 183-184 Tube deposition, 152-160 Turbidity coefficient, 267-269, 275 Turbulence ... 

Brighton, 20th-22nd April 1999, p.160-4 SEPARATION OF CABLE-PVC USING TRIBO-ELECTRIC CHARGING... 

Another process, associated with flow, is the tribo-electric effect in which electrons are transferred from one molecule to another during flow. This requires contact between donor and acceptor molecules or ions which are then forced apart and retain their charges. As stressed above, these centres are likely to be paramagnetic and should be detected by ESR spectroscopy. This phenomenon is very well established at the electrostatic level for surface charges, but is sometimes hard to distinguish from bond homolysis in several systems (Symons,... 

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