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Dead, point, definition

As Skinner has pointed out [7], there is no evidence for the existence of BFyH20 in the gas phase at ordinary temperatures, and the solid monohydrate of BF3 owes its stability to the lattice energy thus D(BF3 - OH2) must be very small. The calculation of AH2 shows that even if BFyH20 could exist in solution as isolated molecules at low temperatures, reaction (3) would not take place. We conclude therefore that proton transfer to the complex anion cannot occur in this system and that there is probably no true termination except by impurities. The only termination reactions which have been definitely established in cationic polymerisations have been described before [2, 8], and cannot at present be discussed profitably in terms of their energetics. It should be noted, however, that in systems such as styrene-S C/4 the smaller proton affinity of the dead (unsaturated or cyclised) polymer, coupled, with the greater size of the anion and smaller size of the cation may make AHX much less positive so that reaction (2) may then be possible because AG° 0. This would mean that the equilibrium between initiation and termination is in an intermediate position. [Pg.181]

EXTENSIONS AND COMMENTARY A most consistent feature with 2C-N was the fact that in every report, somewhere, there is the note that it somehow came up just a little short of expectations. From the esthetic point of view, the pure salt is yellow rather than the usual white color, so the solutions that are to be consumed are by definition also yellow colored. From the structural point of view, the 4-nitro group, like the 4-bromo group of 2C-B, is a dead-end. It cannot be stretched or compressed or lengthened or shortened. This unique aspect demands that you have to live with what you have, as there are no subtle ways of modifying the molecule. With 2C-B, the end product was a total winner there was no wish to modify it. With 2C-N the end product is something a little less, and there is no way to modify it. [Pg.282]

In Part I of this article we discussed the construction and installation of stationary booby traps, craps that require no motion to cause damage. In Part II we are going into some ideas on Moving Booby Traps, or traps that cause damage due to their movement. Note that placement of these traps as In Part I requires a location that Is a well traveled foot path or an avenue of approach to your hideout or survival shelter. In both instances, camouflage is the key factor to installing an effective trap. I would like to point out that the traps illustrated in this article were all used very effectively against out Armed Forces in Viet Mam, and can be very deadly. They arc definitely not toys to play with. [Pg.79]

Another extreme, oxygen-poor place that may give us a timeline of ancient life-chemistry is, ironically, the Dead Sea. As you may have guessed from aU the water there, the Dead Sea is not quite dead. Its shore is the lowest point on dry land, but life can be found a short distance from that shore at the bottom of the lake, eking out a faint but definite, even encouraging, existence. [Pg.112]

What is the definition of a displaced person In Alexander (1985), he discussed the difficulty of defining the dead and injured. What are the cutoff points of reporting An important agenda for the Integrated Research on Disaster Risk (IRDR) organization, whose goal is to develop trans-disciplinary, muIti-sectorial alliances for in-depth practical disaster risk reduction research studies, and the implementation of effective evidence based disaster risk policies and practice, ... [Pg.891]


See other pages where Dead, point, definition is mentioned: [Pg.148]    [Pg.727]    [Pg.753]    [Pg.16]    [Pg.215]    [Pg.131]    [Pg.35]    [Pg.16]    [Pg.551]    [Pg.619]    [Pg.891]    [Pg.293]    [Pg.210]    [Pg.268]    [Pg.896]    [Pg.731]    [Pg.640]    [Pg.147]    [Pg.184]    [Pg.277]    [Pg.384]    [Pg.89]    [Pg.547]    [Pg.6]    [Pg.9]    [Pg.79]    [Pg.198]    [Pg.131]    [Pg.19]    [Pg.556]    [Pg.150]    [Pg.260]   
See also in sourсe #XX -- [ Pg.14 ]




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