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Electromagnetic displacement

Nonresistive redistribution of energy within the electromagnetic field E, B, described by Ampere s Eq. (9) and leading to an electromagnetic displacement current id... [Pg.346]

The electromagnetic fields of the right- and left-propagating polaritons, respectively, follow the wave equations with the speeds and damping rates of the different frequency components dispersed according to the frequency- and wavevector-dependent complex refractive index n = v/e(k, oj). A typical example of the dispersion of these modes is shown in Fig. 1 for the case of a real permittivity e. The term Ao(r,t) represents the envelope of the wavepacket on the phonon-polariton coordinate A. Note that this phonon-polariton coordinate is a linear combination of ionic and electromagnetic displacements, which both contribute to the polarization... [Pg.529]

D = electromagnetic displacement is the value of B in a vacuum K= the voltage in electrostatic units C = the capacitance of a body = the refractive index. 4 = the cross sectional siuface area... [Pg.398]

The relation (2) can also be obtained by solving the 3s-dlmenslonal dynamical equations of motion of a harmonic lattice and are thereby identified as the normal modes of vibrations of the lattice. As is the case in electromagnetic displacements, it is often convenient to replace the normal modes by an equivalent corpuscular description of the lattice displacements. As a result it is usual to associate a phonon with each of the normal modes. [Pg.497]

Radiometry. Radiometry is the measurement of radiant electromagnetic energy (17,18,134), considered herein to be the direct detection and spectroscopic analysis of ambient thermal emission, as distinguished from techniques in which the sample is actively probed. At any temperature above absolute zero, some molecules are in thermally populated excited levels, and transitions from these to the ground state radiate energy at characteristic frequencies. Erom Wien s displacement law, T = 2898 //m-K, the emission maximum at 300 K is near 10 fim in the mid-ir. This radiation occurs at just the energies of molecular rovibrational transitions, so thermal emission carries much the same information as an ir absorption spectmm. Detection of the emissions of remote thermal sources is the ultimate passive and noninvasive technique, requiring not even an optical probe of the sampled volume. [Pg.315]

There are four (4) major types of pumps (I) positive displacement, (2) dynamic (kinetic), (3) lift, and (4) electromagnetic. Piston pumps are positive displacement pumps. The most common centrifugal pumps are of dynamic type ancient bucket-type pumps are lift pumps and electromagnetic pumps use electromagnetic force and are common in modern reactors. Canned pumps are also becoming popular in the petrochemical industiy because of the drive to minimize fugitive emissions. Figure 10-24 shows pump classification ... [Pg.899]

Table 15.5 Recommended limits of voltage and phase displacement errors, applicable for all types of measuring VTs (only electromagnetic and capacitor VTs). Table 15.5 Recommended limits of voltage and phase displacement errors, applicable for all types of measuring VTs (only electromagnetic and capacitor VTs).
In this chapter some important equations for corrosion protection are derived which are relevant to the stationary electric fields present in electrolytically conducting media such as soil or aqueous solutions. Detailed mathematical derivations can be found in the technical literature on problems of grounding [1-5]. The equations are also applicable to low frequencies in limited areas, provided no noticeable current displacement is caused by the electromagnetic field. [Pg.535]

A diatomic molecule placed in an electric field of the type present in an electromagnetic wave experiences an induced dipole M at any instant due to the displacement of the electrons with respect to the relatively massive nuclei under the influence of the applied field E. [Pg.297]

Mossbauer resonance of Zn to study the influence of the gravitational field on electromagnetic radiation. A Ga ZnO source (4.2 K) was used at a distance of 1 m from an enriched ZnO absorber (4.2 K). A red shift of the photons by about 5% of the width of the resonance line was observed. The corresponding shift with Fe as Mossbauer isotope would be only 0.01%. The result is in accordance with Einstein s equivalence principle. Further gravitational red shift experiments using the 93.3 keV Mossbauer resonance of Zn were performed later employing a superconducting quantum interference device-based displacement sensor to detect the tiny Doppler motion of the source [66, 67]. [Pg.262]

To illustrate the use of the vector operators described in the previous section, consider the equations of Maxwell. In a vacuum they provide the basic description of an electromagnetic field in terms of the vector quantifies the electric field and 9C the magnetic field The definition of the field in a dielectric medium requires the introduction of two additional quantities, the electric displacement SH and the magnetic induction. The macroscopic electromagnetic properties of the medium are then determined by Maxwell s equations, viz. [Pg.254]

Inductive Potentiometric Displacement Measurement distributed electromagnetic parameters Micro-Epsilon vipSENSOR industrial use, productions plants, OEM - sensor... [Pg.259]

The concept of potential energy in mechanics is one example of a scalar field, defined by a simple number that represents a single function of space and time. Other examples include the displacement of a string or a membrane from equilibrium the density, pressure and temperature of a fluid electromagnetic, electrochemical, gravitational and chemical potentials. All of these fields have the property of invariance under a transformation of space coordinates. The numerical value of the field at a point is the same, no matter how or in what form the coordinates of the point are expressed. [Pg.107]

Close to this limit the displacements of the two types of atom have opposite sign and the two types of atom vibrate out of phase, as illustrated in the lower part of Figure 8.10. Thus close to q = 0, the two atoms in the unit cell vibrate around their centre of mass which remains stationary. Each set of atoms vibrates in phase and the two sets with opposite phases. There is no propagation and no overall displacement of the unit cell, but a periodic deformation. These modes have frequencies corresponding to the optical region in the electromagnetic spectrum and since the atomic motions associated with these modes are similar to those formed as response to an electromagnetic field, they are termed optical modes. The optical branch has frequency maximum at q = 0. As q increases slowly decreases and... [Pg.239]

According to electromagnetic theory, any time a charge capacitor changes its value a displacement current is generated, expressed as I = dQ/dt = CdV/dt + VdC/dt. [Pg.87]

The model fundamental to all analyses of vibrational motion requires that the atoms in the system oscillate with small amplitude about some defined set of equilibrium positions. The Hamiltonian describing this motion is customarily taken to be quadratic in the atomic displacements, hence in principle a set of normal modes can be found in terms of these normal modes both the kinetic energy and the potential energy of the system are diagonal. The interaction of the system with electromagnetic radiation, i.e. excitation of specific normal modes of vibration, is then governed by selection rules which depend on features of the microscopic symmetry. It is well known that this model can be worked out in detail for small molecules and for crystalline solids. In some very favorable simple cases the effects of anharmonicity can be accounted for, provided they are not too large. [Pg.137]

The primary means of transfer of energy to the fluid that causes flow are gravity, displacement, centrifugal force, electromagnetic force, transfer of momentum, mechanical impulse, and a combination of these energy-transfer mechanisms. Displacement and centrifugal force are the most common energy-transfer mechanisms in use. [Pg.24]

There are four (4) major types of pumps (1) positive displacement, (2) dynamic (kinetic), (3) lift, and (4) electromagnetic. Piston pumps are positive displacement pumps. The most common centrifugal... [Pg.24]

Angular displacement sensed by differential transformers speed indication from electromagnetic sensor on output shaft of drive motor G M G M... [Pg.223]


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Electromagnetic fields displacement vector

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