Inhomogeneity causes

However, before extrapolating the arguments from the gross patterns through the reactor for homogeneous reactions to solid-catalyzed reactions, it must be recognized that in catalytic reactions the fluid in the interior of catalyst pellets may diSer from the main body of fluid. The local inhomogeneities caused by lowered reactant concentration within the catalyst pellets result in a product distribution different from that which would otherwise be observed. 

Figure 12 shows the stress-strain curves of IER at various temperatures. A strain-induced reinforcing effect is not observed at temperatures above -10 °C. This fact may be due to network inhomogeneities caused by imperfect crosslinking. 

The addition of a liquid matrix, usually glycerol, improves the reproducibility of the mass spectra because inhomogeneities caused by analyte and matrix co-crystallisation are avoided. In some cases, it also enhances signal intensity and resolution. However, analytes can also be desorbed from dry surfaces [7 9]. 

The mass calibration law gives mass measurement accuracy of ca. 2 ppm and a precision of ca. 1 ppm. Errors are still systematic, but the measurements are much less sensitive to space charge effects than those made with the cubic cell. One possible cause of the systematic errors may be magnetic field inhomogeneity caused by... 

Fig. 3. Fourier transform of the current induced by the cyclotron motion of 6 ions. The magnetic inhomogeneity causes the frequency to decrease with increasing cyclotron energy...

We have already hinted at two ways to measure T. In cases where the observed line width is due solely to effective (field-inhomogeneity-caused) spin-spin relaxation, the reciprocal of the halfwidth of the peak is T [Eq. (3.12)]. Also, in Section 3.4 we noted that the envelope of the FID signal follows exponential decay governed by T. In principle, we could measure the amount of time (t W2) required for the FID signal to decay to exactly half its initial magnitude (M, = i Mq), at which point Eq. (3.14b) gives... 

Self-Poisoning and Aging of Pd-Ag/Al203 in Semi-Hydrogenation of 1,3-Butadiene Effects of Surface Inhomogeneity Caused by Hydrocarbonaceous Deposits... 

It is not difficult to understand that if the internal area has caverns of current lines these functions still depend on the formation conductivity only. In fact, such inhomogeneities cause the appearance of electrical charges within the internal area, the density of which is directly proportional to the primary electrical field, i.e. frequency. Respectively, the secondary electric field, currents and finally the magnetic field, which are due to these charges, are directly proportional to the frequency also, and therefore functions given by equations 8.8-8.11 are not subjected to the influence caused by the presence of inhomogeneities. 

Since the total unoxidized nitrogen technique gave excellent reproducibility for membrane filtered Bay water, it would seem that the poor reproducibility of the technique for unfiltered samples is because of inhomogeneity caused by uneven distribution of suspended matter. 

Fig. 3.9. Examples of an artifacts inhomogeneities caused by the long-term use of a CR cassette (ghost)...

A miscible polymer blend is one for which the miscibihty and homogeneity extend down to the molecular level, so that there is no phase separation. An immiscible blend is one for which phase separation occurs, as described in the next section. An immiscible blend is called compatible if it is a useful blend wherein the inhomogeneity caused by the different phases is on a small enough scale not to be apparent in use. (Blends that are miscible in certain useful ranges of composition and temperature, but immiscible in others, are also sometimes called compatible blends.) Most blends are immiscible and can be made compatible only by a variety of compatibilisation techniques, which are described in section 12.2.4. Such compatibilised blends are sometimes called polymer alloys. 

In short fibre reinforced composites with aligned or randomly distributed fibres, cracks initiate at flaws, such as pores or in resin-rich areas with local strain inhomogeneities caused by improper fibre alignment or at fibre ends. 

The extensive properties of the overall system that is not in equilibrium, such as volume or energy, are simply the sums of the (almost) equilibrium properties of the subsystems. This simple division of a sample into its subsystems is the type of treatment needed for the description of irreversible processes, as are discussed in Sect. 2.4. Furthermore, there is a natural limit to the subdivision of a system. It is reached when the subsystems are so small that the inhomogeneity caused by the molecular structure becomes of concern. Naturally, for such small subsystems any macroscopic description breaks down, and one must turn to a microscopic description as is used, for example, in the molecular dynamics simulations. For macromolecules, particularly of the flexible class, one frequently finds that a single macromolecule may be part of more than one subsystem. Partially crystalhzed, linear macromolecules often traverse several crystals and surrounding liquid regions, causing difficulties in the description of the macromolecular properties, as is discussed in Sect. 2.5 when nanophases are described. The phases become interdependent in this case, and care must be taken so that a thermodynamic description based on separate subsystems is still valid. 

The third major limitation is that the analysis process itself can change the composition of the surfaces to be analyzed. The two most common t5 es of this problem are analysis beam-induced damage and inhomogeneities caused by the sputtering process, which is used often to probe past the topmost surface of the sample. 

Therefore one might expect that in microgravity conditions the marked optical inhomogeneities caused by a strong convection would be fixed with the "Pion-M" shadow device, whereas small inhomogeneities caused by a weak motion would be detected with an interferometer after delivering the cuvette back to Earth. 

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