Initiator rests

Qa = FArT, with / T being the total excess of redox species). In absence of adsorption of reactants, and assuming that the second potential pulse returns to the initial resting value rest (see Fig. 4.3), Eqs. (4.54) and (4.64) can be written as... 

From the point of view of the polymerization process, bulk (mass) polymerization produces the purest PVC because only initiators and vinyl chloride are used in the process. Bulk polymerization is capable to yield 99.9% pure polymer. In suspension polymerization, a suspending agent is added in addition to initiator, which decreases the purity of suspension PVC to about 99.8%. Microsuspension polymer contains emulsifier and its piuity can be approximately 98.8%. Emulsion polymer may contain more emulsifier and initiator rests and its purity can be estimated as 98%. All these results are quite good for commercial product and PVC can be considered as a relatively pure polymer. More admixtures are usually introduced on the compounding stage from various contaminations and brought together with additives. 

The presence of a multicolour electrochromic effect in rare-earth diphthalo-cyanines was first reported in 1970 by Moskalev et al. . Lutetium diphthalocyanine, LuH(Pc)2, has been studied extensively at Rockwell International Corporation by Nicholson and co-workers . This material may display different colours when polarized either anodically (red, orange) or cathodically (blue, violet) from its initial rest potential. The initially green complex film is obtained by vacuum evaporation. The anodic reaction occurs by the insertion of anions into the film and extraction of electrons rather than by loss of protons. The cathodic reaction, leading to blue and violet products, occurs by the insertion of cations. When protons are present in the electrolyte, the reaction is the following . 

We consider a rigid spherical contaminant particle of radius and density initially resting on a substrate smface and interacting with a liquid droplet under quasi-static conditions (see Figme 5.4). Four forces are involved in this interaction particle weight F, contact line force hydrostatic force F, and buoyancy force F, defined as follows ... 

Typical chain imperfections num- ber/1000 VC 6-8 (head-to-head), 0.1-0.4 (initiator rests) ... 

At the time when Wiener and Rosenblueth formulated their model no reaction-diffusion equations of excitable media were available. Therefore, they simply postulated that the medium consists of elements which can be found in three distinct states of rest, excitation and recovery. After a perturbation, an element goes from the state of rest into the state of excitation, stays there for a fixed time, Tg, and goes then into the state of recovery. The latter lasts for a fixed time % during which the element could not be forced back into the excited state even by strong perturbations. When the recovery is completed, the element returns to the initial rest state and could be again excited. The perturbation, transferring the element into the excited state, could be provided by the neighbouring element if it is currently in the state of excitation. 

If we move away from this existence boundary of spiral waves the rotation periods decrease and become comparable with the recovery time of the medium. It means that propagation of the next wave is now influenced by what is left after the propagation of the first wave, since the medium s elements had not enough time to return to the initial rest state. In other words, the coils of such less sparse spirals are interacting with one another. 

It can be seen from eq. (1.5.17) thaf after the collision, the initially resting particle 2 acquire the velocity M2, the direction of which always coincides with the initial velocity of the first particle before collision. However, the velocity direction of the first particle after collision depends upon the mass ratio of both particles. If m < m2 the first particle changes the direction of flight to the opposite one (as can be seen from eq. (1.5.16)). If mj > m2, the direction of motion of both particles after collision is the same. 

At an initially rested electron, weakly bonded to an atom (with its kinetic energy and momentum practically equal to zero), the photon falls with energy bto and a momentum Me. In this case, the above-mentioned conservation laws in this case look like ... 

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