SATURATION TIME

Using this equation, the flow of the reaction was followed by registering the frequency shift as a function of reaction time. Typical dependencies are shown in Figure 38 (Facci et al. 1994). As one can see, the curves tend to come to saturation (saturation time depends on film thickness). On the other hand, the plateau level in all cases corresponds well to the value resulting from simple calculation of the number of cadmium atoms available for the reaction in each sample. Numerical data of such estimates are presented in Table 8. The available amount of cadmium atoms was estimated in this case, taking into ac-... 

Anandamide is inactivated in two steps, first by transport inside the cell and subsequently by intracellular enzymatic hydrolysis. The transport of anandamide inside the cell is a carrier-mediated activity, having been shown to be a saturable, time- and temperature-dependent process that involves some protein with high affinity and specificity for anandamide (Beltramo, 1997). This transport process, unlike that of classical neurotransmitters, is Na+-independent and driven only by the concentration gradient of anandamide (Piomelli, 1998). Although the anandamide transporter protein has not been cloned yet, its well characterized activity is known to be inhibited by specific transporter inhibitors. Reuptake of 2-AG is probably mediated by the same facilitating mechanism (Di Marzo, 1999a,b Piomelli, 1999). 

There is a so-called dry mercerisation process [275] in which the fabric is padded with caustic soda liquor at 20-25 °C and then dried in a stenter at about 130 °C. An immersion time in the pad trough of 7-10 seconds is sufficient but the goods need a total saturation time in the alkaline liquor of 30-40 seconds, i.e. from the nip to entry into the drying zone. 

At longer saturation times the STDs exhibit a rather complex dependence on a number of factors including free ligand conformation and correlation time, and protein direct and indirect effects (Scheme 2). As a result, the relative intensities in the STD spectrum can sometimes vary with the saturation time. 

Finally, a saturation-transfer screening (using short saturation times) of the protein resonance envelope to identify irradiation frequencies that yield large STDs may be of some aid in the identification of residues within the binding pocket, and in assignments for the calculations. 

X by the terrace width a/s, y by the distance / over which the saturated value of a/ reaches the terrace width squared, a/sy, and t by the corresponding saturation time 4 we should arrive at an isotropic, dimensionless equation, i.e.. 

Note that in the notation of Fig. 18.6, CA becomes the aqueous concentration in the pores of the particle aggregate, C, while Cg becomes the time-constant fluid concentration C°. For simplicity we consider only the case where the initial concentration in the sphere is zero (CA = 0). The dissolved concentration in the sphere, C (r,t), follows from Eq. 18-33 by putting CA = 0 and replacing C by C°. The half-saturation time tm is given by Eq. 18-37 (D replaced by the effective diffusivity... 

Up to now steady state NOEs have been considered, i.e. when one signal is saturated for a long time with respect to T of the nucleus on which NOE is going to be measured. Let s consider here what happens when the saturation time is short and variable. The resulting NOE is called truncated NOE [17] because not enough time is left for full polarization transfer. These experiments are of fundamental importance for the measurement of pi, for evaluating cross relaxation, and to avoid or to measure spin diffusion. 

For irradiation times of J short with respect to the relaxation time of / the NOE extent is independent of the relaxation time of the nucleus and provides a direct measurement of time required to saturate signal J is not negligible compared with t, the response of the system is not linear [18]. The truncated NOE is independent of paramagnetism as it does not depend on p/, which contains the electron spin vector S in the R[m term, and only depends on gkj), which does not contain S. If then the steady state NOE is reached, the value of p/ can also be obtained. This is the correct way to measure p/ of a nucleus, provided saturation of J can be considered instantaneous. In general, measurements at short t values minimize spin diffusion effects. In fact, in the presence of short saturation times, the transfer of saturation affects mainly the nuclei directly coupled to the one whose signal is saturated. Secondary NOEs have no time to build substantially. As already said, this is more true in paramagnetic systems, the larger the R[m contribution to p/. 

In this type of experiment the NOE buildup tends to disappear with p/. In the steady state case, the saturation time is always long enough to allow spin / to cross-relax with other spins, even if pr is large. In transient experiments, the cross relaxation with spin / is by itself limited in time and, pj being the same, cross relaxation with other spins is drastically limited. In any case, spin diffusion is limited in that region of time in which NOE is growing (Fig. 7.6). Truncated and transient NOEs performed with short NOE buildup times are efficient in quenching spin diffusion. 

The measured cross-sectionally averaged liquid holdup (i.e. measured liquid saturation times the bed voidage) are consistent with previously reported results [4], For a similar packing structure, Illiuta and Larachi [4] found liquid holdups, as calculated by their mechanistic model and compared with the reported experimental results, slightly lower than the values obtained in this study. However, there are some differences between the two studies this work was performed in a smaller diameter column ( 30 cm versus... 

Development of a conditioning film. This process should depend on surface properties of the substratum and on the charge and polarity of the sorbed matter. It is a relatively fast [half-saturation times of 5-72 s (Armstrong... 

GMPCPP. While the EpoA and DDM experiments report on the early events of ligand binding to nonpolymerized tubulin, the peloruside A experiments report on its association to polymerized MT. Transferred NOESY data were analyzed quantitatively following the FRM approach and were consistent with the B conformation. The binding epitope of peloruside A was deduced from STD experiments, that with short saturation times (<500 ms) displayed signal enhancements of protons H2, H8, H17, H19-H24, and the three methoxy rings. 

Figure la shows the current AIR increase on the dose of the P-irradiation. Saturation time increased from 5 up to 20 min when the radiation intensity is increased. Relaxation time remains constant 1 h in all cases. The linear increase of Cgo single crystal conductivity on intensity is revealed (Fig. lb). 

The MDT is infinite because the entire dose is not dissolved. Therefore, the term mean saturation time, MDTS, [122] has been suggested as more appropriate when we refer only to the actually dissolved portion of dose,... 

The saturation time is roughiy inverseiy proportionai to the feed concentration. Thus, for a suspension of poiystyrene particies in water, the saturation time changes from 10 to 4 min when the oonoentration changes from 0.5 to 1.0 mass/mass% feed [85]. 

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