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Field energy density

The unique feature in spontaneous Raman spectroscopy (SR) is that field 2 is not an incident field but (at room temperature and at optical frequencies) it is resonantly drawn into action from the zero-point field of the ubiquitous blackbody (bb) radiation. Its active frequency is spontaneously selected (from the infinite colours available in the blackbody) by the resonance with the Raman transition at co - 0I2 r material. The effective bb field mtensity may be obtained from its energy density per unit circular frequency, the... [Pg.1197]

As for crystals, tire elasticity of smectic and columnar phases is analysed in tenns of displacements of tire lattice witli respect to the undistorted state, described by tire field u(r). This represents tire distortion of tire layers in a smectic phase and, tluis, u(r) is a one-dimensional vector (conventionally defined along z), whereas tire columnar phase is two dimensional, so tliat u(r) is also. The symmetry of a smectic A phase leads to an elastic free energy density of tire fonn [86]... [Pg.2558]

In die presence of an electromagnetic field of energy of about our systems can undergo absorjDtive transitions from to E2, extracting a photon from die electric field. In addition, as described by Einstein, die field can induce emission of photons from 2 lo E (given E2 is occupied). Let die energy density of die external field be E(v) dren. [Pg.2858]

The phenomenon of acoustic cavitation results in an enormous concentration of energy. If one considers the energy density in an acoustic field that produces cavitation and that in the coUapsed cavitation bubble, there is an amplification factor of over eleven orders of magnitude. The enormous local temperatures and pressures so created result in phenomena such as sonochemistry and sonoluminescence and provide a unique means for fundamental studies of chemistry and physics under extreme conditions. A diverse set of apphcations of ultrasound to enhancing chemical reactivity has been explored, with important apphcations in mixed-phase synthesis, materials chemistry, and biomedical uses. [Pg.265]

Now Al is the volume, between the plates, that is occupied by the uniform field X. Hence, if the energy of the charged condenser is to be regarded as associated with the field, the energy density lias to be N2/8ir per unit volume. The same result may be reached for a condenser or conductor of any shape. Consider any element of volume dv in a non-uniform field. Since (2) applies to unit volume, if (2) is multiplied by dv, we may take... [Pg.7]

In this chapter the symbol Jt , which stood for the magnetic field in Chapter 9, will be used for energy density. [Pg.581]

In order to interpret the above results, consider the expectation value of the total energy density in the vacuum state, i.e., of the hamiltonian density, Eq. (10-12). There is a contribution J u(x)Al(x) from the external field and a contribution m<0 j (a ) 0)ln 4 (a ) from the induced current, hence to lowest order... [Pg.597]

Intensity at a Point of Superposition (1.17) The measurable physical parameter of an optical wave is its energy density or intensity. If two fields are superimposed, the measured intensity is given by the sum of the individual intensities plus aterm which describes the long term correlation of the field amplifudes. Long ferm means time scales which are large compared to the inverse of the mean frequency uj/2Tt (about 10 s) the time scale is set by the time resolution of the detector. This is why the held product term is expressed in the form of an ergodic mean ). An interferometer produces superimposed helds, the correlation of which carries the desired information about the astronomical source. We will discuss exactly how this happens in the following sections. [Pg.279]

The Navier-Stokes equation and the enthalpy equation are coupled in a complex way even in the case of incompressible fluids, since in general the viscosity is a function of temperature. There are, however, many situations in which such interdependencies can be neglected. As an example, the temperature variation in a microfluidic system might be so small that the viscosity can be assumed to be constant. In such cases the velocity field can be determined independently from the temperature field. When inserting the computed velocity field into Eq. (77) and expressing the energy density e by the temperature T, a linear equahon in T is... [Pg.183]

The fluid model is a description of the RF discharge in terms of averaged quantities [268, 269]. Balance equations for particle, momentum, and/or energy density are solved consistently with the Poisson equation for the electric field. Fluxes described by drift and diffusion terms may replace the momentum balance. In most cases, for the electrons both the particle density and the energy are incorporated, whereas for the ions only the densities are calculated. If the balance equation for the averaged electron energy is incorporated, the electron transport coefficients and the ionization, attachment, and excitation rates can be handled as functions of the electron temperature instead of the local electric field. [Pg.68]

The liquid-liquid interface is not only a boundary plane dividing two immiscible liquid phases, but also a nanoscaled, very thin liquid layer where properties such as cohesive energy, density, electrical potential, dielectric constant, and viscosity are drastically changed along with the axis from one phase to another. The interfacial region was anticipated to cause various specific chemical phenomena not found in bulk liquid phases. The chemical reactions at liquid-liquid interfaces have traditionally been less understood than those at liquid-solid or gas-liquid interfaces, much less than the bulk phases. These circumstances were mainly due to the lack of experimental methods which could measure the amount of adsorbed chemical species and the rate of chemical reaction at the interface [1,2]. Several experimental methods have recently been invented in the field of solvent extraction [3], which have made a significant breakthrough in the study of interfacial reactions. [Pg.361]

CED Cohesive energy density G (1) Gauss unit of magnetic field strength ... [Pg.768]

The mean-field expression for the free-energy density of the polymer solution is therefore [ 13,14]... [Pg.7]

The rolled type batteries are general-purpose batteries with high capacity and good characteristics. Thin film power sources have found a number of specific applications in the fields of portable accumulators with high energy density for application in electronic and integral circuits, sensors, monitors and for medicine [3],... [Pg.494]

We have introduced a gauge fixing term, with the limit e —> 0 being taken after the calculations are carried out.In Eq.(5) A stands for the transverse gauge field and (j) is defined as ip = 4>exp(i y). To obtain the free energy density, Veff = T jV (effective potential), we introduce a shifted field 4> — 4> + and split the Hamiltonian into two parts ... [Pg.302]

The meson fields op, too and po are found by solving a set of equations self-consistently as shown in [11], Also expressions for the energy density, pressure and the entropy density can be found there. The empirical values of the binding energy of nuclear matter and nuclear matter density are reproduced using the above mentioned parameterization. The nuclear matter EOS can be found expressing the chemical potentials as functions of temperature, baryon density... [Pg.81]

Relativistic mean field (RMF) models have been applied successfully to describe properties of rinite nuclei. In general ground state energies, spin-orbit splittings, etc. can be described well in terms of a few parameters ref. [18]. Recently it has lead to the suggestion that the bulk SE is strongly correlated with the neutron skin [19, 20] (see below). In essence the method is based upon the use of energy-density functional (EDF) theory. [Pg.101]

In the absence of electromagnetic and gluonic fields the free energy density F of a homogeneous color superconducting phase near Tc is [10, 17]... [Pg.266]

In the absence of magnetic and chromomagnetic fields and in the homogeneous limit the free energy density becomes... [Pg.266]

An important featnre of the thermal radiation field, described by its energy density Pv, is that it is isotropic that is, the emission is the same in all directions. [Pg.41]


See other pages where Field energy density is mentioned: [Pg.579]    [Pg.579]    [Pg.152]    [Pg.111]    [Pg.423]    [Pg.556]    [Pg.878]    [Pg.1099]    [Pg.4]    [Pg.203]    [Pg.430]    [Pg.581]    [Pg.472]    [Pg.281]    [Pg.125]    [Pg.42]    [Pg.367]    [Pg.371]    [Pg.7]    [Pg.187]    [Pg.15]    [Pg.34]    [Pg.222]    [Pg.256]    [Pg.72]    [Pg.266]    [Pg.27]    [Pg.593]    [Pg.542]    [Pg.76]    [Pg.40]   
See also in sourсe #XX -- [ Pg.91 ]




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