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.
The main cause of ozone depletion and the ozone hole is man-made chemicals, in particular man-made halocarbon refrigerants, solvents, propellants, and foam-blowing agents (chlorofluorocarbon (CFCs), HCFCs, freons, halons), referred to as ozone-depleting substances (ODS).