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Hypothesis strengths

The most direct test of the tensile strength hypothesis would be to compare the value of Tq calculated from the closure point of the isotherm by Equation (3.61) with the tensile strength of the bulk liquid determined directly. Unfortunately, experimental measurement of the tensile strength is extremely difficult because of the part played by adventitious factors such as the presence of solid particles and dissolved gases, so that the values in the literature vary widely (between 9 and 270 bar for water at 298 K, for example). [Pg.158]

It is, however, possible to calculate the tensile strength of a liquid by extrapolation of an equation of state for the fluid into the metastable region of negative pressure. Burgess and Everett in their comprehensive test of the tensile strength hypothesis, plot the theoretical curves of T /T against zjp, calculated from the equations of state of van der Waals, Guggenheim, and Berthelot (Fig. 3.24) (7], and are the critical temperature and critical... [Pg.158]

The evidence in favour of the tensile strength hypothesis accumulated so far is encouraging, but further work is needed before it can be regarded as fully substantiated. In particular, the existence of a minimum value of relative... [Pg.159]

In formulating an explanation of this enhanced adsorption, there are several features to be accounted for the increase in adsorption occurs without hysteresis the amount of adsorbate involved is relatively small the Kelvin r -values are also small (e.g. for nitrogen, less than 17 A) and the effect is found in a region of relative pressures where, according to the simple tensile strength hypothesis, capillary condensate should be incapable of existence. [Pg.163]

The real world of Sn reactions is not quite as simple as the discussion has so far suggested. The preceding treatment in terms of two clearly distinct mechanisms, SnI and Sn2, implies that all substitution reactions will follow one or the other of these mechanisms. This is an oversimplification. The strength of the dual mechanism hypothesis and its limitations are revealed by these relative rates of solvolysis of alkyl bromides in 80% ethanol methyl bromide, 2.51 ethyl bromide, 1.00 isopropyl bromide, 1.70 /er/-butyl bromide, 8600. Addition of lyate ions increases the rate for the methyl, ethyl, and isopropyl bromides, whereas the tert-butyl bromide solvolysis rate is unchanged. The reaction with lyate ions is overall second-order for methyl and ethyl, first-order for tert-butyl, and first- or second-order for the isopropyl member, depending upon the concentrations. Similar results are found in other solvents. These data show that the methyl and ethyl bromides solvolyze by the Sn2 mechanism, and tert-butyl bromide by the SnI mech-... [Pg.428]

Read the entire laboratory activity. Form a hypothesis about the relative strengths of these four metals as reducing agents, from strongest to weakest. Record your hypothesis on page 154. [Pg.153]

Limits on Particle Charging. The electrical charge carried by a particle resides on the surface. Thus, a fundamental upper limit for particle electrification may be computed by imposing the constraint that the electric field at the surface can not exceed the dielectric strength of dry air, Eb 30 kV/cm. According to this hypothesis, the upper limit upon surface charge density becomes... [Pg.821]

This hypothesis may also be presented mathematically the protein amount in a fresh ccll/tissuc expressed as Pf produces an IHC signal in fresh tissue of I (Pf). When the identical IHC staining plus AR treatment is applied to FFPE tissue section, the IHC signal is J (Pffpe). The degree of retrieval after AR (R%) is calculated as R% = J (Pffpe)/J (Pf) x 100%. The amount of protein in the FFPE tissue may then be derived as follows Pffpe = Pf x R%. In a situation where optimized AR is 100% effective, then the IHC signal would be of equal strength in fresh tissue and FFPE tissue, and Pffpe = Pf. [Pg.92]

According to the law of the minimum. P should only influence the growth and competitive strength of plants if it is the limiting factor. The niche dimension hypothesis predicts that a larger number of limiting resources in a habitat leads to... [Pg.156]

The weak-field hypothesis is also supported by the high spin frequencies of these sources from equation (1), if these sources are in magnetic spin equilibrium then their surface magnetic held strengths are B 108 G (Chakrabarty et al. 2003). [Pg.30]

The relation of the radius and the expected strength of the magnetic field is listed by the use of the hypothesis in Table. 1. Then, it looks to work well for explaining the strength of the magnetic field observed for radio pulsars. However, it does not work for magnetars considering the Schwarzschild radius,... [Pg.242]

Work by Harbour, Chow and Bolton (1974) on the spin adducts of superoxide (or HOO )13 with nitrones paved the way for a number of investigations of superoxide and hydroperoxyl radical chemistry. Harbour and Bolton (1975) used DMPO to trap superoxide formed by spinach chloroplasts in the presence of 02. The signal strength was greatly enhanced when methylviologen was present, consistent with the hypothesis that this bis-pyridinium dication accepts an electron from the primary acceptor of photoprotein I, and then transfers it to molecular oxygen. [Pg.53]

Another hypothesis suggests that the binding of a substrate to an enzyme causes a strain or deformation of some of the bonds in the substrate molecule, which are subsequently broken. The effectiveness of this mechanism depends upon the strength of the binding force and does not necessarily involve any movement of the protein but suggests the idea of a flexible enzyme. [Pg.267]


See other pages where Hypothesis strengths is mentioned: [Pg.159]    [Pg.160]    [Pg.321]    [Pg.199]    [Pg.424]    [Pg.779]    [Pg.411]    [Pg.715]    [Pg.1335]    [Pg.65]    [Pg.187]    [Pg.99]    [Pg.200]    [Pg.200]    [Pg.114]    [Pg.3]    [Pg.486]    [Pg.513]    [Pg.24]    [Pg.44]    [Pg.193]    [Pg.73]    [Pg.481]    [Pg.220]    [Pg.209]    [Pg.16]    [Pg.81]    [Pg.213]    [Pg.42]    [Pg.246]    [Pg.283]    [Pg.459]    [Pg.203]    [Pg.123]    [Pg.143]   
See also in sourсe #XX -- [ Pg.244 ]




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Bond strength hypothesis

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