Cooperative rings

When methanol interacts with other molecules, there are some characteristic differences to water [36]. For example, methanol can symmetrically bind two HC1 molecules to its lone pairs without significant energy penalty compared to a cooperative ring arrangement [61]. This is not the case for water, because its... 

Figure 12-6F. Ring channel valves. (Used by permission Cooper-Cameron Corporation.)...

Fig. 3.6 Polyamide-DNA binding motifs targeting longer DNA sequences. Overlapped and slipped homodimers depending on the sequence context, six-ring polyamides with central p-Ma residues can bind to DNA as fully overlapped homodimers, recognizing 11 bp, or as slipped homodimers, recognizing 13 bp. Extended hairpin extended conformation increases binding site size (to 9 bp) and enhances binding affinity. Cooperative dimer a cooperatively binding hairpin polyamide can...

Rao JR, JE Cooper (1994) Rhizobia catabolize nod gene-inducing flavonoids via C-ring fission mechanisms. J Bacterial 176 5409-5413. 

The above comparison indicates that the rate acceleration induced by CD is more pronounced than that of the other tertiary nitrogen bases. This fact also indicates that in CD a cooperative effect should exist between the quinuclidine nitrogen and the quinoline ring, The cooperative effect is in force if the modifier is in a shielded form. 

The assembly of two or more subunits to form a superstructure where at least one cooperative intramolecular ring closure takes place permits the assembly of stable complexes using relatively weak interactions. 

The quantum of magnetic flux is only 2.07 x 10-15 Wb, which is approximately equal to the amount of the earth s magnetic field enclosed by a ring of 10p,m in diameter. The Josephson effect is observed when two superconductors are separated by a very thin insulating layer (about 20 nm). Single electrons and Cooper pairs can tunnel through such a layer. The characteristics of the Josephson junction are now used to define the volt and have enabled the uncertainty in the maintained standard to be reduced to 0.1 p,V. 

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