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Large radii

The material is brittle. There are relatively large radii to be obeyed to enable the vacuum envelope to withstand atmospheric pressure, and tubes must be handled carefully. [Pg.533]

Multiple bonds are formed when an atom forms a tr-bond by using an sp or sp2 hybrid orbital and one or more ir-bonds by using unhybridized p-orbitals. The side-by-side overlap that forms a ir-bond makes a molecule resistant to twisting, results in bonds weaker than tr-bonds, and prevents atoms with large radii from forming multiple bonds. [Pg.238]

The model is found to be most appropriate for contact between low-elastic-moduli materials with large radii when the work of adhesion is high. In comparison, the following model assumes that the surface forces extend over a finite range and act in the region just outside the contact. It is found to be more appropriate for systems with small radii of curvature, low work of adhesion, and high modulus [12]. [Pg.20]

The polarity of the interior of the channel, usually lower than in the case of ionophores, often prevents complete ion dehydration which results in a decrease in the ion selectivity of the channel and also in a more difficult permeation of strongly hydrated ions as a result of their large radii (for example Li+). [Pg.458]

At large radii the widths of the Bragg layers converges asymptotically to the conventional (Cartesian) quarter-wavelength condition. Mathematically, this can be explained by noting that for large radii the Bessel function can be approximated by a sinusoidal function divided by square root of the radius. From the physical... [Pg.322]

The analysis of different astrophysical phenomena associated with compact X-ray sources, seems to indicate in some case the existence of neutron stars with large radii in the range of 12 - 20 km and in some other cases the existence of compact stars with small radii in the range of 6 - 9 km (Bombaci 1997 Li et al. 1999a Poutanen Gierlinski 2003 Bombaci 2003). Clearly, this possibility is a natural outcome of our scenario, where two different families of compact stars, the pure hadronic stars and the quark stars (HyS or SS), may exist in the universe. [Pg.368]

Assuming RX J1856.5-3754 to be a pure hadronic star and 4U 1728-34 an hybrid or a strange star, we see from our results plotted in Fig. 6, that this possibility can be realized as a natural consequence of our scenario. Thus, we find that the existence of quark stars (with small radii) does not exclude the possible existence of pure hadronic stars (with large radii), and vice versa. [Pg.369]

The solids conveying data indicate that two competing factors are controlling the rates. The rate reduction caused by a decrease in the cross-sectional area perpendicular to the flight for the large-radii screw is the most obvious factor. As the radii of the flights are increased, the area perpendicular to the flight tip decreases and... [Pg.166]

Figure 5.30 a) Schematic of the for warding forces for a channel with small radii, and b) schematic of the forwarding forces for a channel with large radii... [Pg.167]

The parts produced were in specification and did not have the splay defect. When the press was switched between different colored resins, the purge time was very short and typically required less than 20 parts. The higher compression ratio and compression rate screw combined with channels that had large radii provided a constant plastication rate and no detectable degradation of the resin. [Pg.520]

Soft species easy to oxidize (bases) or reduce (acids) high polarizability large radii small differences in electronegativities between the acceptor and donor atoms low charge densities at acceptor and donor sites often have low-lying empty orbitals (bases) often have a number of d electrons (acids). [Pg.106]

To calculate the total pore volume it is necessary to measure the total adsorbate volume at a relative pressure above the point where the hysteresis loop closes. In general, a relative pressure as close to unity as possible should be chosen in order to include the large radii pores in the measurement. For example, grams of nitrogen are adsorbed at P/Pq = 0.99 then the corresponding volume of pores Fp and the largest pore radii r are given by... [Pg.61]

To avoid swirl, elbows should be well separated and have large radii of curvature. If this is not possible then the flowmeter should be sited at least 40 pipe diameters downstream of fittings causing asymmetric flow only and a minimum of 100 pipe diameters downstream when swirl is likely to occur0 S). There should also be at least 10 pipe diameters allowed downstream of the meter free of any obstruction or fitting. If the flow is laminar then these distances should be doubled. [Pg.450]

The JKR approximation works well for high adhesion, large radii of curvature and compliant materials but may underestimate surface forces. An alternative theory have been developed by Derjaguin, Muller, Toporov (DMT) to include noncontact adhesion forces acting in a ring-shaped zone around the contact area [81]. On the other hand, the DMT approximation constrains the tip-sample geometry to remain Hertzian, as if adhesion forces could not deform the surfaces. The DMT model applies to rigid systems with small adhesion and radius of curvature, but may underestimate the contact area. For many SFM s, the actual situation is likely to lie somewhere between these two models [116]. The transition between the models their applicability for SFM problems were analysed elsewhere [120,143]. [Pg.100]

Figure 20.2 Illustration of how finite size artifacts lead to concentration mismatches in the bulk (A) RNA phosphate-counterion radial distribution functions for the Tar—Tar complex in an 80 A box of 800 mm NaCl. The anion concentration is 15% different than the cation concentration at large separations. (B) RNA phosphate-counterion radial distribution functions for the Tar—Tar complex in a 120-A box of 800 mm NaCl. The anion and cation concentrations agree with each other to within 1% at large radii. Taken from Chen et al. (2009). Figure 20.2 Illustration of how finite size artifacts lead to concentration mismatches in the bulk (A) RNA phosphate-counterion radial distribution functions for the Tar—Tar complex in an 80 A box of 800 mm NaCl. The anion concentration is 15% different than the cation concentration at large separations. (B) RNA phosphate-counterion radial distribution functions for the Tar—Tar complex in a 120-A box of 800 mm NaCl. The anion and cation concentrations agree with each other to within 1% at large radii. Taken from Chen et al. (2009).

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See also in sourсe #XX -- [ Pg.520 ]




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