Effective coupling factor

These resonances determine the effective coupling factor kea of the device. 

IVR in tlie example of the CH clnomophore in CHF is thus at the origin of a redistribution process which is, despite its coherent nature, of a statistical character. In CHD, the dynamics after excitation of the stretching manifold reveals a less complete redistribution process in the same time interval [97]. The reason for this is a smaller effective coupling constant between the Fenni modes of CHD (by a factor of four) when... 

Salt flux across a membrane is due to effects coupled to water transport, usually negligible, and diffusion across the membrane. Eq. (22-60) describes the basic diffusion equation for solute passage. It is independent of pressure, so as AP — AH 0, rejection 0. This important factor is due to the kinetic nature of the separation. Salt passage through the membrane is concentration dependent. Water passage is dependent on P — H. Therefore, when the membrane is operating near the osmotic pressure of the feed, the salt passage is not diluted by much permeate water. 

The contribution to the stress from electromechanical coupling is readily estimated from the constitutive relation [Eq. (4.2)]. Under conditions of uniaxial strain and field, and for an open circuit, we find that the elastic stiffness is increased by the multiplying factor (1 -i- K ) where the square of the electromechanical coupling factor for uniaxial strain, is a measure of the stiffening effect of the electric field. Values of for various materials are for x-cut quartz, 0.0008, for z-cut lithium niobate, 0.055 for y-cut lithium niobate, 0.074 for barium titanate ceramic, 0.5 and for PZT-5H ceramic, 0.75. These examples show that electromechanical coupling effects can be expected to vary from barely detectable to quite substantial. 

The Jahn-Teller community has lost one of our illustrious members with the death of Frank Ham on December 12, 2002. Phrases such as The Ham effect , Ham factors and Ham quenching are terms that frequently appear in any article in which the Jahn-Teller effect or vibronic coupling is involved. I would like to record my own personal thoughts about Frank and on behalf of the whole Jahn-Teller community. 

Since the leakage factor can be easily calculated from Ti relaxation data, and ys/y is constant, that only leaves the determination of smax before the coupling factor can be directly accessed. For solutions of radicals where Heisenberg exchange is prominent, Emax must be measured as a function of concentration and extrapolated to infinite concentration where smax 26,50 pQr jmmobilized or tethered radicals, nitrogen nuclear spin relaxation effectively mixes the hyperfine states in virtually all cases (small peptides may be an exception) and smax 1 can safely be assumed. 56 Alternately, the determination of smax can be avoided... 

Notice that in both case (d) and case (e) there is no molecular projection quantum number. An example of case (e) coupling, probably the first, has been observed [60] for vibration rotation levels of the HeKr+ ion which lie very close to the dissociation limit. The Kr+ atomic ion has L = 1 and S= 1/2, so that. Ja is 3/2 or 1 /2, and the spin orbit interaction is strong. When a very weak bond is formed with a He atom,. Ja remains a good quantum number, at least for the most weakly bound levels, but there are nevertheless series ofrotation levels, with rotational energy BR(R + 1). The details are described in chapter 10, where we show that case (e) coupling is identified, both by the observed pattern of the rotational levels, and by the measured Zeeman effects and effective g factors for individual rotational levels. 

The direction of the magnetic field defines the space-fixed p = 0 (or Z) direction. Equation (8.239) represents a very simplified version, in that it neglects the nuclear and rotational Zeeman effects, as well as the second-order effects of spin-orbit coupling, none of which are negligible. Nevertheless (8.239) will allow us to derive theoretical values for the first-order effective g-factors, for comparison with the experimental spectra [43]. The required matrix elements of (8.239) in a case (b) hyperfine-coupled basis are as follows ... 

We have already shown the importance of the Zeeman effect, both in identifying the J quantum numbers involved in each line, and in providing effective g-factors for the levels. These g-factors serve as additional labels for each level, and provide information concerning the best angular momentum coupling scheme. We now develop the theory of the Zeeman effect in Hund s case (c). 

For the effective coupling of amino acid residues to the polymer-bound peptide chain, the reaction should be carried out in solvents which swell the resin. Wieland et al. determined the swelling factors for a 2% cross-linked polystyrene-bound Boc-Phe resin in different solvents152>. The volumes of 1 g of this Boc-Phe resin after treatment for 50 hours in different solvents are given in Table 1. These values show that in the case of the polystyrene resin, swelling is minimum in very polar solvents (like methanol) or in very nonpolar solvents (like hexane) and is greatest in chlorinated solvents (like methylenechloride). 

ZnO is a wide band gap semiconductor, which is used for various applications. Based on textured ZnO films one can build highly effective piezo field emitters. On the other hand ZnO is a very effective electron-excited phosphor. ZnO films easily withstand electron fluence more than 1 W/cm. ZnO films doped with Al, Ga, or In have a low resistivity of about 10 " Qcm and a high transparency of about 90%. This is sufficient for applications as a front contact in solar cells, liquid crystal displays etc. Dielectric ZnO films have a high electromechanical coupling factor that allow using ZnO in various surface acoustic wave (SAW) devices such as delay lines, delay-line filters, resonators, transducers and SAW convolvers. 

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