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Maxwell relationships application

This result, that the low frequency limit of the in phase component of the viscosity equates to the viscosity of the dashpot, means that for a single Maxwell model it is possible to replace rj by rj(0). Thus far we have concentrated on the description of experimental responses to the application of a strain. Similar constructions can be developed for the application of a stress. For example the application of an oscillating stress to a sample gives rise to an oscillating strain. We can define a complex compliance J which is the ratio of the strain to the stress. We will explore the relationship between different experiments and the resulting models in Section 4.6. [Pg.112]

Beyond the simple thin surfactant monolayer, the reflectivity can be interpreted in terms of the internal structure of the layer, and can be used to determine thicker layers and more complex surface structures, and this can be done in two different ways. The first of these uses the optical matrix method [18, 19] developed for thin optical films, and relies on a model of the surface structure being described by a series or stack of thin layers. This assumes that in optical terms, an application of Maxwell s equations and the relationship between the electric vectors in successive layer leads to a characteristic matrix per layer, such that... [Pg.92]

The temperature coefficient a corresponds to the negative molar entropy and the pressure coefficient P to the molar volume according to Maxwell relations. Anticipating these relationships can help with remembering the mentioned rules but for a basic knowledge and most applications they are not mandatory. [Pg.50]

Many theoretical and empirical models have been proposed to predict the effective thermal conductivity of two phase mixtures. Comprehensive review articles have discussed the applicability of many of these models that appear to be more promising [34-36]. First, using potential theory. Maxwell [20] obtained a simple relationship for the conductivity of randomly distributed and non-interacting homogeneous spheres in a homogeneous medium. Maxwell model is good for low solid concentrations. Relative thermal conductivity enhancement (ratio of the effective thermal conductivity keffO nanofluid to base fluid kj) is. [Pg.143]

Chemical thermodynamics and kinetics provide the formalism to describe the observed dependencies of chemical-conformational reactions on the external physical state variables temperature, pressure, electric and magnetic fields. In the present account the theoretical foundations for the analysis of electrical-chemical processes are developed on an elementary level. It should be remarked that in most treatments of electric field effects on chemical processes the theoretical expressions are based on the homogeneous-field approximation of the continuum relationship between the total polarization and the electric field strength (Maxwell field). When, however, conversion factors that account for the molecular (inhomogeneous) nature of real systems are given, they are usually only applicable for nonpolar solvents and thus exclude aqueous solutions. Therefore, in the present study, particular emphasis is placed on expressions which relate experimentally observable system properties (such as optical or electrical quantities) with the applied (measured) electric field, and which include applications to aqueous solutions. [Pg.99]

First research works on the application of stirring of liquid metal at the time of its solidification in order to improve the castings quality were carried out by Russ Electroofen in 1939 and concerned the casting of non-ferrous metals and their alloys (Wr6bel, 2010). In order to obtain the movement of the liquid metal in the crystallizer in the researches carried out at this period of time and also in the future, a physical factor in the form of a electromagnetic field defined as a system of two fields i.e. an electric and magnetic field was introduced. The mutual relationship between these fields are described by the Maxwell equations (Sikora, 1998). [Pg.540]

Some of the applicable muscle models include the Maxwell, Voigt, Hill and Carlson models (Figure 1). In particular, the Carlson (1957) equation is used in much of this work to describe the stress-velocity relationship of cardiac muscle over the entire cardiac cycle. Min et al. (1978) found very little difference in analyzing ventricular dynamics when he alternately used Carlson s equation only during isotonic contraction and Hill s equation during isovolumic contraction. [Pg.103]

The relationships of the extended set of tools are guaranteed by the extremum character of the characteristic excess functions, and are the consequence of Maxwell s relations. However, application of the similarity theory opens the way to defining the fundamental isotherms and new material parameters. [Pg.150]

The origin of the theory of viscoelasticity may be traced to various isolated researchers in the last decades of the nineteenth Century. This early stage of development is essentially due to the work of Maxwell, Kelvin and Voigt who independently studied the one dimensional response of such materials. The linear constitutive relationships introduced therein are the base of rheological models which are still used in many applications [121]. Their works led to Boltzmann s [122] first formulation of three dimensional theory for the isotropic medium, which... [Pg.240]

On the other hand, the Maxwell fluid model explains the response of complex fluids to an oscillatory shear rate. The frequency-dependent behavior of this model, displayed into linear responses to applied shear rates has been found to be applicable to a variety of complex fluid systems. Although the linear viscoelasticity is useful for understanding the relationship between the microstructure and the rheological properties of complex fluids, it is important to bear in mind that the linear viscoelasticity theory is only valid when the total deformation is quite small. Therefore, its ability to distinguish complex fluids with similar micro- and nanostructure or molecular structures (e.g. linear or branched polymer topology) is limited. However, complex fluids with similar linear viscoelastic properties may show different non-linear viscoelastic properties [31]. [Pg.228]

Maxwell s equations are linear. However, the parameters that describe material properties may become nonlinear in exceptionally strong fields, such as in powerful lasers. In these cases nonlinear terms have to be included. The linear material equations, Eqs. (1.1.6) to (1.1.8), are not applicable to ferroelectric or ferromagnetic substances where the relationship between the electric field strength, E, and the electric displacement, D, or between the magnetic field strength, H, and the magnetic induction, B, are not only nonlinear, but show hysteresis effects as well. In any case. Maxwell s equations are the foundation of electromagnetism, which includes optics and infrared physics. [Pg.4]


See other pages where Maxwell relationships application is mentioned: [Pg.169]    [Pg.113]    [Pg.140]    [Pg.56]    [Pg.71]    [Pg.227]    [Pg.535]    [Pg.216]    [Pg.131]    [Pg.185]    [Pg.4]    [Pg.296]    [Pg.1048]    [Pg.420]    [Pg.40]    [Pg.1]    [Pg.126]    [Pg.1133]    [Pg.188]    [Pg.245]    [Pg.540]    [Pg.1302]    [Pg.1303]    [Pg.602]    [Pg.1113]    [Pg.169]   
See also in sourсe #XX -- [ Pg.115 , Pg.116 ]




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