Mechanical properties of carbon nanotubes Mechanical properties of carbon nanotubes The mechanical properties of carbon nanotubes reveal them as one of the strongest materials in nature. Carbon nanotubes (CNTs) are long hollow cylinders of graphene. Although graphene sheets have 2D symmetry, carbon nanotubes by geometry have different properties in axial and radial directions. It has been shown that CNTs are very strong in the axial direction. Young's modulus on the order of and tensile strength of were obtained. Carbon nanotubes are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively. This strength results from the covalent sp bonds
Early 2000s recession late 2000s. Early 2000s recession The early 2000s recession was a decline in economic activity which mainly occurred in developed countries. The recession affected the European Union during 2000 and 2001 and the United States in 2002 and 2003. The UK, Canada and Australia avoided the recession, while Russia, a nation that did not experience prosperity during the 1990s, in fact began to recover from said situation. Japan's 1990s recession continued. This recession was predicted by economists, because the boom of the 1990s (accompanied by both low inflation and low unemployment) slowed in some parts of East Asia during the