Building stones protecting

Corrosion by atmospheric sulfur dioxide should be considered in the development and evaluation of protective coatings (267,268). Sulfur dioxide and sulfuric acid therefrom are highly damaging to carbonate building stones (269). 

Roofs are a basic element of shelter from inclement weather. Natural or hewn caves, including those of snow or ice, ate early evidence of human endeavors for protection from the cold, wind, rain, and sun. Nomadic people, before the benefits of agriculture had been discovered and housing schemes developed, depended on the availabiUty of natural materials to constmct shelters. Portable shelters, eg, tents, probably appeared early in history. Later, more permanent stmctures were developed from stone and brick. SaUent features depended strongly on the avadabihty of natural materials. The Babylonians used mud to form bricks and tiles that could be bonded with mortars or natural bitumen. Ancient buildings in Egypt were characterized by massive walls of stone and closely spaced columns that carried stone lintels to support a flat roof, often made of stone slabs. 

Keywords silicone resin network, masonry protection, building material, natural stone impregnation, silicone coating of mineral substrates, structure-effect principle of trifunctional silicones... 

Silicon is extremely important as a building block of unicellular algae -diatoms. The main building material of the frustule (the finely sculptured protective surface layer of diatoms) is a float-stone, an opal-like water-containing polymer of silica Diatoms are the only group of organisms whose development is totally dependent on the presence of soluble forms of silica in the environment. When silicon sources run out, DNA replication stops. 

OTHER COMMENTS used in the manufacture of weatherproof and acid-proof mortars and cements, refractory bricks, heat-resistant and chemical-resistant paints, lacquers, and protective coatings for industrial buildings and castings also used in hardening stone useful in arresting decay and disintegration. 

In another reaction, the yellow PAni is back oxidised to the basic green PAni. Therefore in the process of corrosion protection this behaviour is practically available for the build-up or the repairing of the passivating iron layer—or steel, copper, aluminium etc. These properties make a polyaniline primer interesting for hard applications too from falling stones, rocks or other injuries to the lacquer-structure the normally produced pieces began to produce mst at the site of these injuries, but the workpieces treated with PAni-lacquer were continually protected through the shift of the corrosion potential. 

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