Concrete reinforced with fibers (which are usually steel, glass, or plastic fibers) is less expensive than hand-tied rebar, while still increasing the tensile strength many times. The shape, dimension, and length of the fiber are important.
1. ozone hole-an area of the ozone layer (near the poles) that is seasonally depleted of ozone. hole-an opening into or through something. ozone layer, ozonosphere-a layer in the stratosphere (at approximately 20 miles) that contains a concentration of ozone sufficient to block most ultraviolet radiation from the sun.ole-an opening into or through something. ozone layer, ozonosphere-a layer in the stratosphere (at approximately 20 miles) that contains a concentration of ozone sufficient to block most ultraviolet radiation from the sun.
Largest-ever Ozone Hole over Antarctica. A NASA instrument has detected an Antarctic ozone hole (what scientists call an ozone depletion area) that is three times larger than the entire land mass of the United Statesâthe largest such area ever observed. The hole expanded to a record size of approximately 11 million square miles (28.3 million square kilometers) on Sept. 3, 2000. The previous record was approximately 10.5 million square miles (27.2 million square km) on Sept. 19, 1998. The ozone hole's size currently has ...