Particle electromechanics

Jones, T. B., Particle Electromechanics, Cambridge University Press, New York (1995)... 

Jones, T.B., Electromechanics of Particles. Cambridge University Press, Cambridge, 1995. 

The piezoelectric effect is an electromechanical effect in which mechanical evoke and reverse an electric reaction in a ferroelectric material and vice versa. The word piezo has been derived from the Greek piezein which means press . Compounds are composed of positive and negative ions and are electrically neutral as a whole. The fact that electrically charged particles are still present in the crystal can for example be demonstrated by means of the electric... 

Refs. [i] Pohl HA (1978) Dielectrophoresis. Cambridge University Press, Cambridge [ii] Jones TB (1995) Electromechanics of particles. Cambridge University Press, Cambridge [iii] Stephens M, Talary M, Pethig R et al (1996) Bone Marrow Transplant 18 777 [iv] Voldman J (2006) Anna Rev Biomed Eng 8 425... 

The performance of eddy-current separators depends on parameters such as belt speed, rotor speed, and splitter (or splitters) position. Separation is also affected by the characteristics of the feed such as particle size, shape and conductivity, size distribution, density, and moisture. In general, the capacity of eddy-current separators broadly ranges between 1 and 20 tons/hour per 1 m of belt width, depending on the material density and particle size. As electromechanical forces depend on particle size, for efficient separation solid waste stream must be classified into proper size fractions. In general, eddy-current separators process solid waste with particle size between 150 and 3 mm, and, sometimes... 

Lateral capillary forces between vertical cylinders or between spherical particles have been measured by means of sensitive electromechanical balance, piezotransducer balance,and torsion microbalance. Good agreement between theory and experiment has been established. 

Colored pigments or fluorescent UV indicators may be used to inspect for bleedout from adhesives during and after cure. They may also be used to inspect for particles of cured adhesives that may have detached, migrated and contaminated other parts of an electronic assembly. Particles of electrically conductive or nonconductive adhesives can cause failures in microelectronic assembhes, gyros, accelerometers, or other electromechanical systems and are especially serious in space electronics. Rhodamine B which is pink to red in both the visible and UV regions and 2,6-distyrylpyridine which is visually colorless but intensely blue in the UV region are effective indicators in some adhesives formulations. 

For mechanical lysis, nanostructured filter-Uke contractions are employed in microfluidic channels with pressure-driven cell flow. Prinz et al. utilized rapid diffusive mixing to lyse Escherichia coli cells and trap the released chromosome via dielectrophoresis (DEP). Kim et al. developed a microfluidic compact disk platform for mechanical lysis of cells using spherical particles with an efficiency of approximately 65 % however, this method is difficult to be apphed for single-cell analysis. Lee et al. fabricated nanoscale barbs in a microfluidic chip for mechanical cell lysis by shear and frictional forces. Munce et al. reported a device to lyse individual cells by electromechanical shear force at the entrance of 10 mm separation channels. The contents of individual cells were simultaneously injected into parallel channels for electrophoretic separation, which can be recorded by laser-induced fluorescence OLIF) of the labeled cellular contents. The use of individual separation channels for each cell separation eliminated possible cross-contamination from multiple cell separations in a single channel. 

Induced-charge and second-kind electrokinetic phenomena arise due to electrohydrodynamic effects in the electric double layer, but the term nonlinear electrokinetic phenomena is also sometimes used more broadly to include any fluid or particle motion, which depends nonlinearly on an applied electric field, fit the classical effect of dielectrophoresis mentioned above, electrostatic stresses on a polarized dielectric particle in a dielectric liquid cause dielectro-phoretic motion of particles and cells along the gradient of the field intensity (oc VE ). In electrothermal effects, an electric field induces bulk temperature gradients by Joule heating, which in turn cause gradients in the permittivity and conductivity that couple to the field to drive nonlinear flows, e.g., via Maxwell stresses oc E Ve. In cases of flexible solids and emulsions, there can also be nonlinear electromechanical effects coupling the... 

The droplet is a macrosystem (collective of particles) consisting of structural elements that may be considered as electromechanical oscillators. 

Now, if the electromagnetic force is assumed to be the incident (external) force, which initiates the mechanical disturbance, then the oscillation of the continuum particles (molecules surrounding the droplet—film structure) is described by the differential equation (15.19), where o> is the frequency of the incident oscillations. After a certain time, the oscillations of the free oscillators wo (molecules surrounding the droplet—film stiuctuie) tune with the incident oscillator frequency ft. This process of tuning between free oscillations of the environmental oscillators and the incident oscillations of the electromechanical oscillator can be expressed as... 

Hiamtup, P. Sirivat, A. Jamieson, A. M., Electromechanical Response of a Soft and Flexible Actuator Based on Polyaniline Particles Embedded in a Cross-Linked Poly(dimethylsiloxane) Network. Mater. Sci. Eng., Part C 2008, 28,1044-1051. 

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