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 hole in the ozone layer happens because the ozone in the stratosphere is destroyed by chlorine and bromine from halogen atoms. These atoms come from man-made halocarbon refrigerator gases (chlorofluorocarbons [CFCs], freons and halons) which are emitted at ground level but move up into the ozone layer.zone depletion was observed to increase as emissions of halo-carbons increased. Ozone is a protective layer in the upper atmosphere. It is formed when oxygen molecules absorb short wavelength ultra violet radiations from the sun. Ozone is mostly destroyed by free radicals in the atmosphere.