Resistance origin

Fig. 13. Schematic of a microscopic view of contact interface where constriction resistance originates in the constriction of current flow through the touching metallic junctions (a spots) of the mating surfaces. The arrows and lines indicate the flow of current.

Microbial polysaccharides, 20 573-578 major, 20 574t purification of, 20 574-575 Microbial reductions, 76 401-402 Microbial resistance, origin and spread of, 75 303-304... 

Goode J. and D.J. Chadwick Antibiotic Resistance, Origins, Evolution. Selection and Spread. Vol. 207, John Wiley Sons. Inc.. New York, NY, 1997. 

The resist system which supported the i-line technology for many years in an exclusive manner was so-called diazonaphthoquinone (DNQ)/novolac resists (Fig. 5). This type of resists originally invented for printing by Suss [2] is a two-component system consisting of a novolac resin and a photoactive compound (PAC), diazonaphthoquinone. The novolac resin is soluble in aqueous base in virtue of the acidic phenolic OH functionality. However, the lipophilic diazonaphthoquinone dispersed in the phenolic matrix inhibits the dissolution of the resin film in an aqueous base developer. UV irradiation of the photoactive compound results in formation of a highly reactive carbene, accompanied... 

Note the form of this equation—the mass transfer is proportional to the square of the channel thickness d, and inversely proportional to the diffusion coefficient in the mobile phase Dg,. Both numerator and denominator contain the retention factor k elevated to the same power. This means that the contribution of the mobile-phase mass-transfer term is smallest but finite when the retention factor is 0 (>the analyte is unretained) and increases as the retention factor increases. This is typical for all contributions to the mass-transfer resistance originating in the mobile phase. The actual form of the coefficient that contains the retention factor is a function of the velocity profile in the mobile phase, which was parabolic in the case of the capillary. 

Once again the coefficient is proportional to the square of the thickness of the stationary phase layer dg, and inversely proportional to the diffusion coeflScient in this layer Dg. Ibe power of the retention factor is lower in the numerator than in tte denominator, and there is no constant term in the numerator. This means that this factor is 0 when the analyte is unretained and approadies 0 when the retention factor is very lai. In between it will go through a maximum. This also is typical for all contributions to mass-transfer resistance originating in the stationary phase. 

VE resins offer much better corrosion resistance compared with general purpose UPE resins. The better corrosion resistance originates from the large number of atoms between the ester groups, low concentration of ester groups, and the steric hindrance offered by the pendent methyl group of methacrylic acids. 

We illustrate each form of resistance in Figure 5.7. The rotating friction resistance originates from the friction forces between the surface of the Earth, the set of tires, and the shaft bearings. This friction is proportional to the vehicle s mass, and the value of the coefficient p is around 0.025, based on empirical data. The air resistance is literally the resisting force from air, which is proportional to the squared vehicle speed, V. The value... 

Phenolic resins also qualify for high-performance applications thanks to their excellent weathering and media resistance. Originally developed for military and aerospace applications, today phenolic resin composites are used for filament winding of offshore pipe for the oil and gas industry. Here, polysiloxane-modified phenolic resins are used [709]. 

The water resistance in terms of liquid-phase effects can be expressed as pressure differential sum. Such differences will develop as the resistance originates at motion of gas in the dry apparatus and pressure, which is... 

ASR may be divided into ohmic resistance, R, and electrode polarisation resistance, Rp. The ohmic resistance originates from the electrolyte, the electrodes materials and the current collection arrangement. This is very much dependent on geometric factors such as thickness of the cell components and the detailed geometry of the contact between current collection and electrodes, and between electrodes and electrolyte as current constrictions may be important [41]. The electrode polarisation resistance is further divided into contributions from the various rate-limiting steps. Thus, ASR can be broken down in five terms ... 

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