Stevenson’s group

In subsequent years, Stevenson s group continued the investigation of N-doped CNFs and carbon nanotubes (CNT) grown from ferrocene and pyridine [54, 55]. From these experiments, they concluded that O2 reduction at neutral pH was not catalyzed by surface-bound Fe species. In their last paper [56], they used the... 

When a ketone grows larger it does not necessarily imply that it has two identical alkyl groups at the carbonyl. In case of different alkyls at the carbonyl, Stevenson s rule may also be applied to decide which of them will dominantly be detected as part of the acylium ion and which should preferably give rise to a carbenium ion. Overall, a nonsymmetrical ketone will yield four primary fragment ions in its El mass spectrum... 

Here the Schomaker-Stevenson coefficient c is to be given the value 0.08 A for all bonds involving one first row atom (or two such atoms), the value 0.06 A for bonds between Si, P, or S and a more electronegative atom (not of the first row), 0.04 A for bonds between Ge, As, or Se and a more electronegative atom (not of the first row), and 0.02 A for bonds between Sn, Sb, or Te and a more electronegative atom (not of the first row). The electronegativity correction is not to be made between carbon and the elements of the fifth, sixth, and seventh groups (beyond the first row) it seems likely that another effect (double-bond character, Sec. 9-3) overwhelms it. 

Pauling s revised Schomaker-Stevenson rule Rather, it is clear that steric repulsion alone is sufficient to explain why no methyl-bridged dimer forms the boron atom is too small to accommodate four methyl groups. In a hypothetical dimer (Fig. 3d) the eight Cb Q distances would be only about 2.70 A. In dimeric trimethylaluminum the corresponding distance is 3.23... 

Aslam, S.N. Stevenson, P.C. Hall, D.R. In Advances In Fungal Control Strategies, SCI Pest Management Group, Syngenta, Jealotts Hill, Bracknell, UK 29 May 2003 (2003). 

Finally, for those who find controversy unsettling, I can do no better than quote the heroine of William Boyd s Brazzaville Beach I have taken new comfort and refuge in the doctrine that advises one not to seek tranquility in certainty, but in permanently suspended judgement. From Brazzaville Beach by William Boyd, published by Sinclalr-Stevenson. Reprinted by permission of The Random House Group Ltd. 

The authors gratefully acknowledge the Robert A. Welch Foundation (Grant number W-1552) and the U.S. National Science Foundation (Grant number CHE-0449549) for financial support of our work. We also thank Professors Keith Stevenson and Dick Crooks, as well as their research groups, for a variety of experimental assistance and valuable discussions. 

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