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Standard Theory

Because most applications for micro-channel heat sinks deal with liquids, most of the former studies were focused on micro-channel laminar flows. Several investigators obtained friction factors that were greater than those predicted by the standard theory for conventional size channels, and, as the diameter of the channels decreased, the deviation of the friction factor measurements from theory increased. The early transition to turbulence was also reported. These observations may have been due to the fact that the entrance effects were not appropriately accounted for. Losses from change in tube diameter, bends and tees must be determined and must be considered for any piping between the channel plenums and the pressure transducers. It is necessary to account for the loss coefficients associated with singlephase flow in micro-channels, which are comparable to those for large channels with the same area ratio. [Pg.138]

Standard theories of steric stabilisation assume that the free energy of the system can be expressed as a sum of two terms, volume restriction and osmotic, which are mutually independent. [Pg.224]

The reader can see now that experimental conditions are progressing in such a way that would allow for verifications of the quantum theories of solvent effects. The important theoretical fact is the possibility of recasting the standard theory of solvent effects, based upon classical statistical mechanics, into a more complete quantum mechanical approach. [Pg.311]

In the standard theory the integrated coefficient of spontaneous emission of a transition between two manifolds / and is given by... [Pg.122]

Still, one can use standard packages for attractor states by actually finding a stationary geometry. The problem is that the standard theory does not conceive of confined states. This element is new. It qualitatively simplifies the analyses. But it is not a practical tool yet. However, confinement underlies a severe limitation of the LCAO bonding orbitals as they dissociate in a manner inconsistent with the general confinement property. Barrier less profiles for radical association process can be traced back to a numerical artifact. [Pg.193]

An exposition of the standard theory of lime discounting (Fig. V.2.A) is Tjalling Koopmans, "Stationary ordinal utility and im-... [Pg.183]

The standard theories of chemical kinetics are equilibrium theories in which a Maxwell-Boltzmann distribution of reactants is postulated to persist during a reaction.68 The equilibrium theory first passage time is the TV -> oo limit in Eq. (6), Corrections to it then are to be expected when the second term in this equation is no longer negligible, i.e., when N is not much greater than e — e- )-1. The mean first passage time and rate of activation deviate from their equilibrium value by more than 10% when... [Pg.156]

The authors of this book started working on chemical kinetics more than 10 years ago focusing on investigations of particular radiation - induced processes in solids and liquids. Condensed matter physics, however, treats point (radiation) defects as active particles whose individual characteristics define kinetics of possible processes and radiation properties of materials. A study of an ensemble of such particles (defects), especially if they are created in large concentrations under irradiation for a long time, has lead us to many-particle problems, common in statistical physics. However, the standard theory of diffusion-controlled reactions as developed by Smoluchowski... [Pg.3]

From the theoretical perspective, the need to assess the nature of the Coulom-bic phase transition has led to many activities. Thus, most theories have relied on the RPM as a generic model for the ionic phase transition. From the various theoretical tools for deriving the EOS, only MSA- and DH-based approaches have found wide application. Applications of the HNC, which is a standard theory in general electrolyte thermodynamics, have remained scarce because of numerical problems when approaching phase transitions. However, pure DH and MSA theory are linear theories that fail at low T. It is known for a long time that, at least in parts, this failure can be remedied by accounting for ion pair formation. More recently, it has become clear that at near- and subcritical temperatures, free-ion-ion-pair and ion-pair-ion-pair interactions play a crucial role. Just in this regard, DH theory seems to provide a particularly flexible and transparent scheme for such theoretical extensions. [Pg.36]

It is locally equivalent to Maxwell s standard theory in empty space (but globally disequivalent). This means that it cannot enter in conflict with Maxwell s theory in experiments of local nature. [Pg.250]

Charge transport is one of the important processes that control the speed of the PR index grating formation and the PR sensitivity. According to the standard theory of photorefraction [21], the response time for the formation and erasure of the space-charge field [xr in Eq. (21)] is proportional to the dielectric relaxation... [Pg.270]

Abstract. Muonium is a hydrogen-like system which in many respects may be viewed as an ideal atom. Due to the close confinement of the bound state of the two pointlike leptons it can serve as a test object for Quantum Electrodynamics. The nature of the muon as a heavy copy of the electron can be verified. Furthermore, searches for additional, yet unknown interactions between leptons can be carried out. Recently completed experimental projects cover the ground state hyperfine structure, the ls-2s energy interval, a search for spontaneous conversion of muonium into antimuonium and a test of CPT and Lorentz invariance. Precision experiments allow the extraction of accurate values for the electromagnetic fine structure constant, the muon magnetic moment and the muon mass. Most stringent limits on speculative models beyond the standard theory have been set. [Pg.81]

The dominant interaction within the muonium atom is electromagnetic. This can be treated most accurately within the framework of bound state Quantum Electrodynamics (QED). There are also contributions from weak interaction which arise from Z°-boson exchange and from strong interaction due to vacuum polarization loops with hadronic content. Standard theory, which encompasses all these forces, allows to calculate the level energies of muonium to the required level of accuracy for all modern precision experiments1. [Pg.81]

Precision experiments in muonium provide sensitive tests for the standard theory, in particular of the most advanced field theory, QED. The nature of the... [Pg.82]

Predictions of the values of and 34 from standard theory - dominantly the QED terms - requires values for many atomic constants including m, and Av as well as the calculation of higher order QED radiative corrections. The... [Pg.398]

An approach is developed to incorporate in the standard theory of the double layer the effect of the solvent polarization, This polarization is due to a source of polarization on the surface and to the charges in the diffuse layer. The new equations lead to the conclusion that a diffuse layer can be generated even in the absence of a surface charge as long as there is some source of polarization on the surface, such as a layer of dipoles. The solvent polarization also changes the surface potential. [Pg.470]

The standard theory of colloidal interactions is that of DLYO [29, 30]. They used the primitive model of the electrolyte. Because of the asymmetry in the DH theory, they applied the DH/PB theory to a fluid of charged point ions in a slit to width L. Restricting our attention to the linearized case, the slit profile is... [Pg.563]

Here, two sources of uncertainty become apparent in preparation and measurement of a quantum system they originate precisely from the way the system is prepared (first aspect) and thereafter the interactions leading to the change of quantum state allows for detection (second aspect). These two aspects have not always been well acknowledged (cf. de Muynck [8]). Furthermore, the standard theory requires that each individual material system, once it is measured, be left only in one eigenstate so that the amplitude squared is assigned a statistical interpretation. This sort of transition is named as the collapse of the wavefunction [9]. [Pg.56]

Wigner in 1963 [11] concluded that the standard theory of measurement remains the only one that is compatible with the QM. This is a strong statement made by one of the pioneers that should be nuanced by supplementing with another comment made in the same paper "This is a legitimate statement if we acknowledge that the interpretation is sustained by the idea that QM describes the states of objects (entities) in real space. A measurement put the object in a particular eigenstate of the observable one selects the linear superposition collapse as it were [11]."... [Pg.56]


See other pages where Standard Theory is mentioned: [Pg.878]    [Pg.98]    [Pg.201]    [Pg.409]    [Pg.442]    [Pg.21]    [Pg.21]    [Pg.6]    [Pg.217]    [Pg.73]    [Pg.153]    [Pg.115]    [Pg.122]    [Pg.351]    [Pg.201]    [Pg.235]    [Pg.236]    [Pg.249]    [Pg.540]    [Pg.73]    [Pg.136]    [Pg.240]    [Pg.165]    [Pg.329]    [Pg.26]    [Pg.57]    [Pg.83]    [Pg.93]    [Pg.100]    [Pg.419]    [Pg.978]    [Pg.3]   
See also in sourсe #XX -- [ Pg.160 ]




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