Self compensation effect

In I-, 2-, and 6-nitrodichlorobenzene the energy of activation is much increased. As the chlorine atom removed is in a lateral position this cannot be explained as a screening or steric hindrance effect if, however, we trace out the field produced by the three neighbouring dipoles accurately we obtain a perfectly symmetrical configuration, and it is easy to see that a self-compensated field of this kind due to several dipoles will require an increased... 

It is assumed that each crystal is surrounded completely by gas at a uniform concentration, which means that direct transfer between crystals is neglected and that all the crystal surface is accessible to the gas. The 2 assumptions are self-compensating, but one could expect serious errors if there is significant crystal-binder agglomeration. It is assumed further that all the crystals are uniformly-sized spheres, mainly for mathematical simplicity. Of course, 5A crystals are in fact cubic, but with the corners cut off, so that the spherical approximation is not unreasonable. The uniform size is a more drastic assumption, which is discussed below. The diffusion processes in both crystals and pores are assumed to be governed by Pick s law. For the pores, an effective diffusivity Dp) is used, which can be related to the bulk gas diffusivity Dq) by the relation ... 

Approximately doubling the rate of A1 addition in titration increased the average value of k2" by 0.21 log unit at pH 5.00 and by 0.15 log unit at pH 5.20 (Table V). This suggests that the system may not have been totally self-compensating for this factor. However, the effect on the rate constants is probably within uncertainty limits that arc imposed by various other factors that affect the experimental results. 

Historically the underestimation of the role and magnitude of the self-cooling effect in kinetic studies of thermal decomposition has turned out to be one of the most important reasons which hindered interpretation of the T-S effect and, to some extent, the compensation effect, and promoted some misconceptions [19, 26-28], based on the confidence in infallibility of the second-law method in determination of thermochemical parameters (the enthalpy and entropy for decomposition reactions). 

In this monograph, the kinetics of carbonate decompositions have been considered in several sections concerning the formation of oversaturated vapour and nucleation (Sect. 2.4), the structure of the solid product (Sect. 2.6), the influence of the reaction mode and stoichiometry on the molar enthalpy (Sect. 5.4), the experimental estimation of the self-cooling (Sect. 6.3), the T-S effect (Sect. 7.3), the variation of the enthalpy of decomposition with temperature (Sect. 8.2), the compensation effect (Chapter 12), and the determination of the absolute rates of decomposition of single crystals and powders in a vacuum and in air (Sects. 15.1 and 15.5). 

Accuracy of the data required must be established. Errors in the interpretation of results may arise either from errors of measurement or from factors that are not normally subject to measurement. The effect of these errors depends to a large extent on the intended use of the test results. If test data are used to predict performance of the same evaporator under slightly different conditions, most of the normal errors are self-compensating. If test data for one effect of an evaporator are to be used in the design of a new evaporator, even minor errors can be of great importance. Accurate data is necessary when comparing actual peformance to that expected. 

From Figure 9.3, the 90° MTN cell exhibits a good dark state, similar to a transmissive TN cell because of the self-phase compensation effect of the orthogonal boundary layers. However, its maximum reflectance is only 88%. On the other hand, the 75° MTN cell has nearly 100% reflectance, but its dark state has a slight light leakage. The contrast ratio at 5 Vrms is around 100 1. This is because the boundary layers are not perfectly compensating each other. 

The ceramic multi-layer coating effectively confines fission products at 1400°C for a long period and at 1600°C in the course of a few hours. At such temperatures the removal of residual heat can be performed by natural convection, conduction and radiation on a passive basis. Given the characteristic coated particle size (the diameter of 2-4 mm), the heat from coated particle fuel is transferred to the coolant with a delay of only 0.1 s. Therefore, the core of a reactor with boiling water coolant that directly cools such coated fuel particles would provide a very rapid self-compensation of practically any positive reactivity if it is introduced not faster than in 0.1 s. 

Certain features of fast reactors, such as lack of poisoning effects, low values of the negative temperature reactivity effect, and self-compensation of bum-up reactivity swing by the secondary plutonium build up, make it possible for the operating reactivity margin in the... 

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