245 reported on the synthesis of linear but alsobranched polymers prepared by di-, tri-, and tetra-alkyne andazide monomers like the combination of tripropargylamine(B 3)and(dihydroxymethyl)(diazidomethyl)amine(A 2)(com-pare the general outline in Scheme 17).
When discussing mineral formations in caves, we often talk about stalactites and stalagmites. A stalactite is an icicle-shaped formation that hangs from the ceiling of a cave, and is produced by precipitation of minerals from water dripping through the cave ceiling. Most stalactites have pointed tips.
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.It is extremely soft, cleaves with very light pressure and has a very low specific gravity.hat remains is a nearly pure carbon material that crystallizes into mineral graphite. This graphite occurs in seams that correspond to the original layer of coal. When mined the material is known as amorphous graphite. The word amorphous is actually incorrect in this usage as it does have a crystalline structure.