Viscous loading

The external forces may be optical tweezers, microneedles, or the viscous load of the substance that is carried. These generalized forces create motion, characterized by an average velocity v, and average rate of ATP consumption JT. Molecular motors mostly operate far from equilibrium, and the velocity and rate of ATP consumptions are not linear functions of the forces. However, in the vicinity of the linear region, where A kBT, linear relations hold... 

Data interpolated from points of 20-Hz resolution. Admittance maximum (at resonant frequency). Afis the shift in center frequency with respect to the value on initial exposure to H2O (corrected for viscous load of electrolyte). Column A Data for first exposure to electrolyte without electrochemical cycling Column B Open circuit data after electrochemical cycling at each concentration. Gravimetric surface coverage 20 x 10 mol cm. ... 

Assume that molecular motors are isothermal and in local equilibrium. For the motor/filament system is induced by an external force/ext such as viscous friction forces between the motor and the bath solvent or viscous load of an object that is carried (Julicher et al., 1997). 

Hunt A.J., Gittes E, and Howard J. 1994. The force exerted by a single kinesin molecule against a viscous load. Biophys. J. 67 766-781. 

Elastomeric shield materials (ESM) have been developed as low density flexible ablators for low shear appHcations (49). General Electric s RTV 560 is a foamed silicone elastomer loaded with silicon dioxide [7631-86-9] and iron oxide [1317-61 -9] particles, which decomposes to a similar foam of Si02, SiC, and EeSiO. Silicone resins are relatively resistant to thermal decomposition and the silicon dioxide forms a viscous Hquid when molten (50) (see... 

Figure 16 (145). For an elastic material (Fig. 16a), the resulting strain is instantaneous and constant until the stress is removed, at which time the material recovers and the strain immediately drops back to 2ero. In the case of the viscous fluid (Fig. 16b), the strain increases linearly with time. When the load is removed, the strain does not recover but remains constant. Deformation is permanent. The response of the viscoelastic material (Fig. 16c) draws from both kinds of behavior. An initial instantaneous (elastic) strain is followed by a time-dependent strain. When the stress is removed, the initial strain recovery is elastic, but full recovery is delayed to longer times by the viscous component.

Tissue Conditioners. Tissue conditioners are gels designed to alleviate the discomfort from soft-tissue injury, eg, extractions. Under a load, they exhibit viscous flow, forming a soft cushion between the hard denture and the oral tissues. The polymer in tissue conditioners is often the same as that used for resilient liners. The liquid is a plasticizer containing an alcohol of low volatility (219,220). 

Automatic filters are made with either viscous-coated or dry filter media. However, the cleaning or disposal of the loaded medium is essentially continuous and automatic. In most such devices the air passes horizontally through a movable filter curtain. As the filter loads with dust, the curtain is continuously or intermittently advanced to expose clean media to the air flow and to clean or dispose of the loaded medium. Movement of the curtain can be provided by a hand crank or a motor drive. Movement of a motor-driven curtain can be actuated automatically by a differential-pressure switch connected across the filter. 

Figure 9.7. Types of deformalional response as a result of a fixed load being imposed betweem times to and ti (a), (b) Ordinary elastic material, (c) Highly elastic material, (d) Viscous material...

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