It reveals a new method of generating dual frequency by using heptagonal
slot and triangular patches in the structure.
Covalent bonding of six carbon atoms at the vertices of a hexagon observed in sheet structure of graphene was found to be responsible for forming a variety of structures like--seamless multi and single walled tubular (nanotubes), spherical cagey (fullerenes) and branching tubules when combined with additional pentagonal and heptagonal
Plate la is heptagonal
and 2a is hexagonal, the former being the largest epithecal plate and about twice as large as the latter.
It was history-making for another reason too - it was, according to the DCB, the only heptagonal
coin in circulation in the world.
The building's unique heptagonal
structure contributes dynamic angles and multiple exposures, offering exceptional light and views.
The compact old part of town was built in the late Medieval era with two city gateways, a councilhouse with one of the oldest indoor-theatres of central Switzerland, and three heptagonal
fountains with bronze figures of more recent date.
By overlapping different numbers of sections, the students created regular pyramids with different bases: triangular, rectangular, pentagonal, hexagonal, and heptagonal