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Rest mass description

Dayhoff [50] suggested that one might measure a rest mass of photon by designing a low-frequency oscillator from an inductor-capacitor (LC) network. The expected frequency can be calculated from Maxwell s equations, and this may be used to give an effective wavelength for photons of that frequency. He claimed that one would have a measure of the dispersion relationship at low frequencies. Williams [51] calculated the effective capacitance of a spherical capacitor using Proca equations. This calculation can then be generalized to any capacitor with the result that a capacitor has an additional term that is quadratic in the area of the plates of the capacitor. However, this term is not exactly the one that Dayhoff referred to. But it seems to be a very close description of it. One can add two identical capacitors C in parallel and obtain the result... [Pg.605]

Note that the formal superposition, Eq. (1.11), reproduces a physical attribute, yielding the present derivation of special relativity a tangible conception outside a purely abstract understanding. Another important observation, associated with the biorthogonal setting of the system, entails that the analysis shows that the formulation turns out to be nonstatistical. We notice moreover that the description for a zero rest mass particle (photon) corresponds to a degenerate singularity of the equations since... [Pg.7]

Table 3.1. Contributions of various physical effects (non-relativistic, Bieit, QED, and beyond QED, distinct physical contributions shown in bold) to the ionization energy and the dipole polarizability a of the helium atom, as well as comparison with the experimental values (all quantities are expressed in atomic units i.e.. e = 1. fi = 1, mo = 1- where iiiq denotes the rest mass of the electron). The first column gives the symbol of the term in the Breit-Pauli Hamiltonian [Eq. (3.72)] as well as of the QED corrections given order by order (first corresponding to the electron-positron vacuum polarization (QED), then, beyond quantum electrodynamics, to other particle-antiparticle pairs (non-QED) li,7T,. ..) split into several separate effects. The second column contains a short description of the effect. The estimated error (third and fourth columns) is given in parentheses in the units of the last figure reported. [Pg.150]

The path diagram provides the big picture for mass flow from a species viewpoint. This is a fundamentally different vision from the equipment-oriented description of a process (the flowsheet), in which the big picture is lost. The path diagram can also be used to determine the effect on the rest of the diagram of manipulating any node. In addition, as will be shown later, it provides a systematic way for identifying where to remove the pollutants and to what extent they should be removed. [Pg.158]

In terms of the process, very little has been achieved. The mass transfer limitations still exist although emulsification has solved the problem partially, but not without creating another problem downstream in separation of the product from the rest of the stream and the issue still needs further work. The IP portfolio contains very few real process concepts. The patented material refers to a BDS process several times, but the process referred to, is no more than a simple description of the pH, temperature, etc., and the particular use of a given biocatalyst in an application. Some protected subject matter concerns the integration of a bioprocess into the flow sheet of the refinery, but again those are no more than theoretical scheme proposed for implementation, with no actual evidence with real feedstocks. [Pg.365]

Ideal reactors can be classified in various ways, but for our purposes the most convenient method uses the mathematical description of the reactor, as listed in Table 14.1. Each of the reactor types in Table 14.1 can be expressed in terms of integral equations, differential equations, or difference equations. Not all real reactors can fit neatly into the classification in Table 14.1, however. The accuracy and precision of the mathematical description rest not only on the character of the mixing and the heat and mass transfer coefficients in the reactor, but also on the validity and analysis of the experimental data used to model the chemical reactions involved. [Pg.481]

There is no a prion justification for Eq. (11-30) since the form of Eq. (11-11) (and not simply the coefficients) depends on the assumption of creeping flow. Moreover, the form of the equation is open to criticism for example, momentum arguments suggest that the added mass term be written pVI2)d di U)/dt. However, Eq. (11-30) is the form for which Eqs. (11-31) and (11-32) were determined (05), and appears to give an accurate description of the motion of spheres from rest as demonstrated in Fig. 11.7. Curve 1 shows the predictions... [Pg.297]

Engineering systems mainly involve a single-phase fluid mixture with n components, subject to fluid friction, heat transfer, mass transfer, and a number of / chemical reactions. A local thermodynamic state of the fluid is specified by two intensive parameters, for example, velocity of the fluid and the chemical composition in terms of component mass fractions wr For a unique description of the system, balance equations must be derived for the mass, momentum, energy, and entropy. The balance equations, considered on a per unit volume basis, can be written in terms of the partial time derivative with an observer at rest, and in terms of the substantial derivative with an observer moving along with the fluid. Later, the balance equations are used in the Gibbs relation to determine the rate of entropy production. The balance equations allow us to clearly identify the importance of the local thermodynamic equilibrium postulate in deriving the relationships for entropy production. [Pg.115]

Included also in this chapter is a qualitative description of separations based on intraphase mass transfer (dialysis, permeation, electrodialysis, etc.) and discussions of the physical property criteria on which the choice of separation operations rests, the economic factors pertinent to equipment design, and an introduction to the synthesis of process flowsheets. [Pg.397]

That is, it is not rotating. We wUl convince ourselves that our SFCS is inertial by measuring how a pointlike mass (assumed to not be interacting with the rest of the spaceship) moves. If it moves along a straight line with a constant velocity, then the SFCS is inertial. In a non-inertial coordinate system, the description of the physical phenomena in the molecule will be different. [Pg.1147]

The formulation of Hooke s law rests on the assumption of infinitesimally small deformations. Its apphcation to the simple model of a mass connected with a spring results in a hnear force law and to the well known harmonic oscillation. Investigating even with very modest means the behavior of a real system of this sort shows that the limits of accuracy of this simple description are quite narrow indeed. A more general and accurate description will have to be a nonlinear one. This, in fact mrns out to be tme for all material properties, e.g. dielectric properties and the simple relation (4.2) is valid only for small fields and is an approximation in the same way as Hooke s law (3.51). If we are looking close enough we find that all phenomena aetually are nonlinear, which means that the response of even simple systems to an external influence cannot be precisely described by a direct proportionaUty. [Pg.101]

This is a step in a process that was recently developed at AstraZeneca. The original process description specified 10 mole equivalents of chlorine to be used. A reaction mechanism was postulated suggesting that only 3 mole equivalents were required, therefore the rest was effectively wasted. Attention was focused around improving the mass transfer of the chlorine. Laboratory experiments showed that the reaction kinetics is extremely fast and highly exothermic. Scale-up mixing utilities, provided with DynoChem, were used to provide required agitation rates in the laboratory to ensure the gas was fully dispersed. [Pg.1086]


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See also in sourсe #XX -- [ Pg.14 ]




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Rest mass

Restful

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