us airways flight 1549 landed in the hudson river.
us airways flight 1549 landed in the hudson river.
when did the plane land in the hudson river?
us airways flight 1549
Na
Na
a fair number of higher polycycles containing the biphenylene nucleus have also been prepared, some having considerable antiaromatic character. in general, additional 6-membered rings add further aromatic character, and additional 4-membered and 8-membered rings add antiaromatic character. however, the exact natures of the additions and fusions greatly affect the perturbations of the biphenylene system, with many fusions resulting in counter-intuitive stabilization by [4n] rings, or destabilization by 6-membered rings. this has led to significant interest in the systems by theoretical chemists and graph theoreticians. even a complete 2-dimensional carbon sheet with biphenylene-like subunits has been proposed
biphenylene