Wood equation

We call the equations 18a and 18b the Allan-Lamboum equations, although they are actually modifications of Wilkins, Pike and Fickett-Wood equations... 

Fiekett-Wood Equation of State. See Con-stant-/3 and Con scan t-y Equations of State , Vol 4, pp D275-L D275-R... 

Fickett-Wood equation of state see Constant- 3 and constant-a equations of state 4 D275... 

The Wood equation (33) is suitable for calculating Tg values for emulsion copolymers. 

A logarithmic form of this equation is given by Pochan et al. Other expressions include the Wood equation the Kelley-Bueche expression the Gordon-Taylor equation and the DiMarzio-Gibbs equation None of these Equations directly take into account the specific interactions within a blend. 

The moisture content of wood is usually calculated in terms of its dry weight. The fractional moisture content m is defined as the ratio of the mass W of removable water to the dry mass W of the wood (Equation 1). 

The speed and attenuation of sound in a food material are of no practical value in themselves but only as they relate to other relevant material properties. Fundamentally, wavenumber is related to material properties via the Wood equation (5) ... 

It is relatively easy to determine an empirical correlation line to measure the solids content of a mixture of soluble and insoluble fats (a good straight line was shown up to ( ) = 0.5), but these authors (14) were also able to show that the Wood equation (Eq. 2) may also be used to give some theoretical basis to the measurement. For a two-phase system with small density differences between the phases and particle sizes less than ultrasonic wavelength, the density (p) and adiabatic compressibility (K) in Equation 2 are given by volume fraction (< )) weighted averages K = (1 - ( ))Kj + ( )K2 and p = (1 - ( ))P[ + ( )P2 (subscripts 1 and 2 refer to the... 

Figure 2.25 Plot of Tg against composition for PPO/PS blends according to (a) the linear equation, (b) the Fox equation, and (c) the Wood equation. Circles represent experimental points (data of Problem 2.32).

In Fig. 46 the dependences of glass transition temperature Tg, determined by the thermomechanical method, on formal contents cform are shown for the indicated copolymers. As one can see, the dependences Tg(cform) course is different for these copolymers. For APESF the values Tg are situated above additive glass transition temperature, for CP-OFD-lO/P-1 — lower and for diblock-copolymers CP-OFD-lO/OSF-10 the dependence Tg(cform) has sigmoid character. Such course of the dependences Tg(cform) for the indicated copolymers supposes different change Kh with copolymers composition. The value KM can be estimated according to tlie well-known Gordon-Talor-Wood equation [143] ... 

The description of the historic Gordon-T ay lor and Wood equations for the glass transition of solutions and copolymers can be found in Gordon M, Taylor IS (1952) Ideal Copolymers and the Second-order Transitions of Synthetic Rubbers. I. Noncrystalline Copolymers. J Appl Chem 2 493-500 Wood LA (1958) Glass Transition Temperatures of Copolymers. 1 Polymer Sci 28 319-330 for the relationship to the volume changes, see Kovacs AJ (1964) Glass Transition in Amorphous Polymers. Phenomenological Study. Fortschr Hochpolym Forsch 3 394-508. 

Replacing the volume fractions above with weight fractions, one obtains the so-called Wood Equation, which is often used for random copolymer systems (Wood 1958). 

Gordon-Tailor-Wood equation W = comonomer molar fraction wk = week yr = year c = velocity... 

The Wood equation has been criticised in that it predicts zero yield at parturition, which, in the light of the development of the secretory potential of the mammary gland at parturition, is obviously not so. A number of alternatives have been put forward. Most have been more complex and have proved to give less satisfactory performance. That of Emmans and Fisher 1986... 

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